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Su P, Wu H, Huang Y, Lu X, Yin J, Zhang Q, Lan X. The Hoof Color of Australian White Sheep Is Associated with Genetic Variation of the MITF Gene. Animals (Basel) 2023; 13:3218. [PMID: 37893942 PMCID: PMC10603658 DOI: 10.3390/ani13203218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 09/28/2023] [Accepted: 10/06/2023] [Indexed: 10/29/2023] Open
Abstract
Studying the characteristics of mammalian hoof colors is important for genetic improvements in animals. A deeper black hoof color is the standard for breeding purebred Australian White (AUW) sheep and this phenotype could be used as a phenotypic marker of purebred animals. We conducted a genome-wide association study (GWAS) analysis using restriction site associated DNA sequencing (RAD-seq) data from 577 Australian White sheep (black hoof color = 283, grey hoof color = 106, amber hoof color = 186) and performed association analysis utilizing the mixed linear model in EMMAX. The results of GWAS demonstrated that a specific single-nucleotide polymorphism (SNP; g. 33097911G>A) in intron 14 of the microphthalmia-associated transcription factor (MITF) gene was significantly associated with the hoof color in AUW sheep (p = 9.40 × 10-36). The MITF gene plays a key role in the development, differentiation, and functional regulation of melanocytes. Furthermore, the association between this locus and hoof color was validated in a cohort of 212 individuals (black hoof color = 122, grey hoof color = 38, amber hoof color = 52). The results indicated that the hoof color of AUW sheep with GG, AG, and AA genotypes tended to be black, grey, and amber, respectively. This study provided novel insights into hoof color genetics in AUW sheep, enhancing our comprehension of the genetic mechanisms underlying the diverse range of hoof colors. Our results agree with previous studies and provide molecular markers for marker-assisted selection for hoof color in sheep.
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Affiliation(s)
- Peng Su
- Tianjin Aoqun Animal Husbandry Co., Ltd., Tianjin 301607, China; (P.S.)
- Key Laboratory of Animal Genetics Breeding and Reproduction of Shanxi Province, College Animal Science and Technology, Northwest A&F University, Yangling 712100, China
- National Germplasm Center of Domestic Animal Resources, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
| | - Hui Wu
- College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Yangming Huang
- Key Laboratory of Animal Genetics Breeding and Reproduction of Shanxi Province, College Animal Science and Technology, Northwest A&F University, Yangling 712100, China
| | - Xiaofang Lu
- Tianjin Aoqun Animal Husbandry Co., Ltd., Tianjin 301607, China; (P.S.)
- Tianjin Aoqun Sheep Industry Academy Company, Tianjin 301607, China
| | - Jing Yin
- Tianjin Aoqun Animal Husbandry Co., Ltd., Tianjin 301607, China; (P.S.)
- Tianjin Aoqun Sheep Industry Academy Company, Tianjin 301607, China
| | - Qingfeng Zhang
- Tianjin Aoqun Animal Husbandry Co., Ltd., Tianjin 301607, China; (P.S.)
- Tianjin Aoqun Sheep Industry Academy Company, Tianjin 301607, China
| | - Xianyong Lan
- Key Laboratory of Animal Genetics Breeding and Reproduction of Shanxi Province, College Animal Science and Technology, Northwest A&F University, Yangling 712100, China
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Kalds P, Zhou S, Gao Y, Cai B, Huang S, Chen Y, Wang X. Genetics of the phenotypic evolution in sheep: a molecular look at diversity-driving genes. Genet Sel Evol 2022; 54:61. [PMID: 36085023 PMCID: PMC9463822 DOI: 10.1186/s12711-022-00753-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Accepted: 08/29/2022] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND After domestication, the evolution of phenotypically-varied sheep breeds has generated rich biodiversity. This wide phenotypic variation arises as a result of hidden genomic changes that range from a single nucleotide to several thousands of nucleotides. Thus, it is of interest and significance to reveal and understand the genomic changes underlying the phenotypic variation of sheep breeds in order to drive selection towards economically important traits. REVIEW Various traits contribute to the emergence of variation in sheep phenotypic characteristics, including coat color, horns, tail, wool, ears, udder, vertebrae, among others. The genes that determine most of these phenotypic traits have been investigated, which has generated knowledge regarding the genetic determinism of several agriculturally-relevant traits in sheep. In this review, we discuss the genomic knowledge that has emerged in the past few decades regarding the phenotypic traits in sheep, and our ultimate aim is to encourage its practical application in sheep breeding. In addition, in order to expand the current understanding of the sheep genome, we shed light on research gaps that require further investigation. CONCLUSIONS Although significant research efforts have been conducted in the past few decades, several aspects of the sheep genome remain unexplored. For the full utilization of the current knowledge of the sheep genome, a wide practical application is still required in order to boost sheep productive performance and contribute to the generation of improved sheep breeds. The accumulated knowledge on the sheep genome will help advance and strengthen sheep breeding programs to face future challenges in the sector, such as climate change, global human population growth, and the increasing demand for products of animal origin.
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Affiliation(s)
- Peter Kalds
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
- Department of Animal and Poultry Production, Faculty of Environmental Agricultural Sciences, Arish University, El-Arish, 45511 Egypt
| | - Shiwei Zhou
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
- College of Veterinary Medicine, Northwest A&F University, Yangling, 712100 China
| | - Yawei Gao
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
| | - Bei Cai
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
| | - Shuhong Huang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
| | - Yulin Chen
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
- International Joint Agriculture Research Center for Animal Bio-Breeding, Ministry of Agriculture and Rural Affairs, Yangling, 712100 China
| | - Xiaolong Wang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
- International Joint Agriculture Research Center for Animal Bio-Breeding, Ministry of Agriculture and Rural Affairs, Yangling, 712100 China
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Kunene LM, Muchadeyi FC, Hadebe K, Mészáros G, Sölkner J, Dugmore T, Dzomba EF. Genetics of Base Coat Colour Variations and Coat Colour-Patterns of the South African Nguni Cattle Investigated Using High-Density SNP Genotypes. Front Genet 2022; 13:832702. [PMID: 35747604 PMCID: PMC9209731 DOI: 10.3389/fgene.2022.832702] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 03/25/2022] [Indexed: 11/29/2022] Open
Abstract
Nguni cattle are a Sanga type breed with mixed B. taurus and B. indicus ancestry and proven resistance to ticks, diseases and other harsh conditions of the African geographical landscape. The multi-coloured Nguni coats have found a niche market in the leather industry leading to breeding objectives towards the promotion of such diversity. However, there is limited studies on the genomic architecture underlying the coat colour and patterns hampering any potential breeding and improvement of such trait. This study investigated the genetics of base coat colour, colour-sidedness and the white forehead stripe in Nguni cattle using coat colour phenotyped Nguni cattle and Illumina Bovine HD (770K) genotypes. Base coat colour phenotypes were categorised into eumelanin (n = 45) and pheomelanin (n = 19). Animals were categorised into either colour-sided (n = 46) or non-colour-sided (n = 94) and similarly into presence (n = 15) or absence (n = 67) of white forehead stripe. Genome-wide association tests were conducted using 622,103 quality controlled SNPs and the Efficient Mixed Model Association eXpedited method (EMMAX) implemented in Golden Helix SNP Variation Suite. The genome-wide association studies for base coat colour (eumelanin vs. pheomelanin) resulted into four indicative SNPs on BTA18 and a well-known gene, MC1R, was observed within 1 MB from the indicative SNPs (p < 0.00001) and found to play a role in the melanogenesis (core pathway for melanin production) and the MAPK signalling pathway. GWAS for colour-sidedness resulted in four indicative SNPs, none of which were in close proximity to the KIT candidate gene known for colour-sidedness. GWAS for the white forehead stripe resulted in 17 indicative SNPs on BTA6. Four genes MAPK10, EFNA5, PPP2R3C and PAK1 were found to be associated with the white forehead stripe and were part of the MAPK, adrenergic and Wnt signalling pathways that are synergistically associated with the synthesis of melanin. Overall, our results prove prior knowledge of the role of MC1R in base coat colours in cattle and suggested a different genetic mechanism for forehead stripe phenotypes in Nguni cattle.
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Affiliation(s)
- Langelihle Mbali Kunene
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Scottsville, South Africa
| | | | - Khanyisile Hadebe
- Agricultural Research Council, Biotechnology Platform, Onderstepoort, South Africa
| | - Gábor Mészáros
- Division of Livestock Sciences, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Johann Sölkner
- Division of Livestock Sciences, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Trevor Dugmore
- KZN Department of Agriculture and Rural Development, Pietermaritzburg, South Africa
| | - Edgar Farai Dzomba
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Scottsville, South Africa
- *Correspondence: Edgar Farai Dzomba,
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Gebreselassie G, Liang B, Berihulay H, Islam R, Abied A, Jiang L, Zhao Z, Ma Y. Genomic mapping identifies two genetic variants in the MC1R gene for coat colour variation in Chinese Tan sheep. PLoS One 2020; 15:e0235426. [PMID: 32817695 PMCID: PMC7444486 DOI: 10.1371/journal.pone.0235426] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Accepted: 06/15/2020] [Indexed: 11/25/2022] Open
Abstract
Coat colour is one of the most important economic traits of sheep and is mainly used for breed identification and characterization. This trait is determined by the biochemical function, availability and distribution of phaeomelanin and eumelanin pigments. In our study, we conducted a genome-wide association study to identify candidate genes and genetic variants associated with coat colour in 75 Chinese Tan sheep using the ovine 600K SNP BeadChip. Accordingly, we identified two significant SNPs (rs409651063 at 14.232 Mb and rs408511664 at 14.228 Mb) associated with coat colour in the MC1R gene on chromosome 14 with −log10(P) = 2.47E-14 and 1.00E-13, respectively. The consequence of rs409651063 was a missense variant (g.14231948 G>A) that caused an amino acid change (Asp105Asn); however, the second SNP (rs408511664) was a synonymous substitution and is an upstream variant (g.14228343G>A). Moreover, our PCR analysis revealed that the genotype of white sheep was exclusively homozygous (GG), whereas the genotypes of black-head sheep were mainly heterozygous (GA). Interestingly, allele-specific expression analysis (using the missense variant for the skin cDNA samples from black-head sheep) revealed that only the G allele was expressed in the skin covered with white hair, while both the G and A alleles were expressed in the skin covered with black hair. This finding indicated that the missense mutation that we identified is probably responsible for white coat colour in Tan sheep. Furthermore, qPCR analysis of MC1R mRNA level in the skin samples was significantly higher in black-head than white sheep and very significantly higher in GA than GG individuals. Taken together, these results help to elucidate the genetic mechanism underlying coat colour variation in Chinese indigenous sheep.
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Affiliation(s)
- Gebremedhin Gebreselassie
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
- Department of Agricultural Biotechnology, Biotechnology Center, Ethiopian Biotechnology Institute, Ministry of Innovation and Technology, Addis Ababa, Ethiopia
| | - Benmeng Liang
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
| | - Haile Berihulay
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
| | - Rabul Islam
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
| | - Adam Abied
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
| | - Lin Jiang
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
| | - Zhengwei Zhao
- Institute of animal science, Ningxia Academy of Agriculture and Forestry Sciences, Ningxia, Yinchuan, China
- * E-mail: (YM); (ZZ)
| | - Yuehui Ma
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing, China
- * E-mail: (YM); (ZZ)
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5
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Gebreselassie G, Berihulay H, Jiang L, Ma Y. Review on Genomic Regions and Candidate Genes Associated with Economically Important Production and Reproduction Traits in Sheep ( Ovies aries). Animals (Basel) 2019; 10:E33. [PMID: 31877963 PMCID: PMC7022721 DOI: 10.3390/ani10010033] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 11/24/2019] [Accepted: 12/20/2019] [Indexed: 12/15/2022] Open
Abstract
Sheep (Ovis aries) is one of the most economically, culturally, and socially important domestic animals. They are reared primarily for meat, milk, wool, and fur production. Sheep were reared using natural selection for a long period of time to offer these traits. In fact, this production system has been slowing the productivity and production potential of the sheep. To improve production efficiency and productivity of this animal through genetic improvement technologies, understanding the genetic background of traits such as body growth, weight, carcass quality, fat percent, fertility, milk yield, wool quality, horn type, and coat color is essential. With the development and utilization of animal genotyping technologies and gene identification methods, many functional genes and genetic variants associated with economically important phenotypic traits have been identified and annotated. This is useful and presented an opportunity to increase the pace of animal genetic gain. Quantitative trait loci and genome wide association study have been playing an important role in identifying candidate genes and animal characterization. This review provides comprehensive information on the identified genomic regions and candidate genes associated with production and reproduction traits, and gene function in sheep.
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Affiliation(s)
- Gebremedhin Gebreselassie
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (G.G.); (H.B.); (L.J.)
- National Germplasm Center of Domestic Animal Resources, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
- Department of Agricultural Biotechnology, Biotechnology Center, Ethiopian Biotechnology Institute, Ministry of Innovation and Technology, Addis Ababa 1000, Ethiopia
| | - Haile Berihulay
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (G.G.); (H.B.); (L.J.)
- National Germplasm Center of Domestic Animal Resources, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
| | - Lin Jiang
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (G.G.); (H.B.); (L.J.)
- National Germplasm Center of Domestic Animal Resources, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
| | - Yuehui Ma
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; (G.G.); (H.B.); (L.J.)
- National Germplasm Center of Domestic Animal Resources, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
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6
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Almathen F, Elbir H, Bahbahani H, Mwacharo J, Hanotte O. Polymorphisms in MC1R and ASIP Genes are Associated with Coat Color Variation in the Arabian Camel. J Hered 2019; 109:700-706. [PMID: 29893870 PMCID: PMC6108395 DOI: 10.1093/jhered/esy024] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 05/18/2018] [Indexed: 11/12/2022] Open
Abstract
Pigmentation in mammals is primarily determined by the distribution of eumelanin and pheomelanin, the ratio of which is mostly controlled by the activity of melanocortin 1 receptor (MC1R) and agouti signaling protein (ASIP) genes. Using 91 animals from 10 Arabian camel populations, that included the 4 predominant coat color phenotypes observed in the dromedary (light brown, dark brown, black, and white), we investigated the effects of the MC1R and ASIP sequence variants and identified candidate polymorphisms associated with coat color variation. In particular, we identified a single nucleotide polymorphism (SNP), found in the coding region of MC1R (901C/T), linked to the white coat color, whereas a 1-bp deletion (23delT/T) and a SNP (25G/A) in exon 2 of ASIP are associated with both black and dark-brown coat colors. Our results also indicate support that the light-brown coat color is likely the ancestral coat color for the dromedary. These sequence variations at the MC1R and ASIP genes represent the first documented evidence of candidate polymorphisms associated with Mendelian traits in the dromedary.
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Affiliation(s)
- Faisal Almathen
- Department of Veterinary Public Health and Animal Husbandry, College of Veterinary Medicine, King Faisal University, Saudi Arabia.,The Camel Research Center, King Faisal University, Saudi Arabia
| | - Haitham Elbir
- The Camel Research Center, King Faisal University, Saudi Arabia
| | - Hussain Bahbahani
- The Department of Biological Sciences, Faculty of Science, Kuwait University, Safat, Kuwait
| | - Joram Mwacharo
- The International Centre for Agricultural Research in the Dry Areas (ICARDA) c/o ILRI-Ethiopia Campus, Addis Ababa, Ethiopia
| | - Olivier Hanotte
- The School of Life Sciences, University of Nottingham, University Park, Nottingham, UK.,LiveGene, International Livestock Research Institute, Addis Ababa, Ethiopia
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Mendoza MN, Raudsepp T, Alshanbari F, Gutiérrez G, Ponce de León FA. Chromosomal Localization of Candidate Genes for Fiber Growth and Color in Alpaca ( Vicugna pacos). Front Genet 2019; 10:583. [PMID: 31275359 PMCID: PMC6593342 DOI: 10.3389/fgene.2019.00583] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 06/04/2019] [Indexed: 12/20/2022] Open
Abstract
The alpaca (Vicugna pacos) is an economically important and cultural signature species in Peru. Thus, molecular genomic information about the genes underlying the traits of interest, such as fiber properties and color, is critical for improved breeding and management schemes. Current knowledge about the alpaca genome, particularly the chromosomal location of such genes of interest is limited and lags far behind other livestock species. The main objective of this work was to localize alpaca candidate genes for fiber growth and color using fluorescence in situ hybridization (FISH). We report the mapping of candidate genes for fiber growth COL1A1, CTNNB1, DAB2IP, KRT15, KRTAP13-1, and TNFSF12 to chromosomes 16, 17, 4, 16, 1, and 16, respectively. Likewise, we report the mapping of candidate genes for fiber color ALX3, NCOA6, SOX9, ZIC1, and ZIC5 to chromosomes 9, 19, 16, 1, and 14, respectively. In addition, since KRT15 clusters with five other keratin genes (KRT31, KRT13, KRT9, KRT14, and KRT16) in scaffold 450 (Vic.Pac 2.0.2), the entire gene cluster was assigned to chromosome 16. Similarly, mapping NCOA6 to chromosome 19, anchored scaffold 34 with 8 genes, viz., RALY, EIF2S2, XPOTP1, ASIP, AHCY, ITCH, PIGU, and GGT7 to chromosome 19. These results are concordant with known conserved synteny blocks between camelids and humans, cattle and pigs.
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Affiliation(s)
- Mayra N. Mendoza
- Programa de Mejoramiento Animal, Universidad Nacional Agraria La Molina, Lima, Peru
| | - Terje Raudsepp
- Molecular Cytogenetics and Genomics Laboratory, Texas A&M University, College Station, TX, United States
| | - Fahad Alshanbari
- Molecular Cytogenetics and Genomics Laboratory, Texas A&M University, College Station, TX, United States
| | - Gustavo Gutiérrez
- Programa de Mejoramiento Animal, Universidad Nacional Agraria La Molina, Lima, Peru
| | - F. Abel Ponce de León
- Department of Animal Science, University of Minnesota, Minneapolis, MN, United States
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8
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Alshanbari F, Castaneda C, Juras R, Hillhouse A, Mendoza MN, Gutiérrez GA, Ponce de León FA, Raudsepp T. Comparative FISH-Mapping of MC1R, ASIP, and TYRP1 in New and Old World Camelids and Association Analysis With Coat Color Phenotypes in the Dromedary ( Camelus dromedarius). Front Genet 2019; 10:340. [PMID: 31040864 PMCID: PMC6477024 DOI: 10.3389/fgene.2019.00340] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 03/29/2019] [Indexed: 12/15/2022] Open
Abstract
Melanocortin 1 receptor (MC1R), the agouti signaling protein (ASIP), and tyrosinase related protein 1 (TYRP1) are among the major regulators of pigmentation in mammals. Recently, MC1R and ASIP sequence variants were associated with white and black/dark brown coat colors, respectively, in the dromedary. Here we confirmed this association by independent sequencing and mutation discovery of MC1R and ASIP coding regions and by TaqMan genotyping in 188 dromedaries from Saudi Arabia and United States, including 38 black, 53 white, and 97 beige/brown/red animals. We showed that heterozygosity for a missense mutation c.901C > T in MC1R is sufficient for the white coat color suggesting a possible dominant negative effect. Likewise, we confirmed that the majority of black dromedaries were homozygous for a frameshift mutation in ASIP exon 2, except for 4 animals, which were heterozygous. In search for additional mutations underlying the black color, we identified another frameshift mutation in ASIP exon 4 and 6 new variants in MC1R including a significantly associated SNP in 3'UTR. In pursuit of sequence variants that may modify dromedary wild-type color from dark-reddish brown to light beige, we identified 4 SNPs and one insertion in TYRP1 non-coding regions. However, none of these were associated with variations in wild-type colors. Finally, the three genes were cytogenetically mapped in New World (alpaca) and Old World (dromedary and Bactrian camel) camelids. The MC1R was assigned to chr21, ASIP to chr19 and TYRP1 to chr4 in all 3 species confirming extensive conservation of camelid karyotypes. Notably, while the locations of ASIP and TYRP1 were in agreement with human-camelid comparative map, mapping MC1R identified a new evolutionary conserved synteny segment between camelid chromosome 21 and HSA16. The findings contribute to coat color genomics and the development of molecular tests in camelids and toward the chromosome level reference assemblies of camelid genomes.
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Affiliation(s)
- Fahad Alshanbari
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| | - Caitlin Castaneda
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| | - Rytis Juras
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| | - Andrew Hillhouse
- Institute for Genome Sciences and Society, Texas A&M University, College Station, TX, United States
| | - Mayra N. Mendoza
- Animal Breeding Program, National Agrarian University La Molina, Lima, Peru
| | | | | | - Terje Raudsepp
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
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9
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Marín JC, Rivera R, Varas V, Cortés J, Agapito A, Chero A, Chávez A, Johnson WE, Orozco-terWengel P. Genetic Variation in Coat Colour Genes MC1R and ASIP Provides Insights Into Domestication and Management of South American Camelids. Front Genet 2018; 9:487. [PMID: 30483307 PMCID: PMC6242857 DOI: 10.3389/fgene.2018.00487] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Accepted: 10/01/2018] [Indexed: 01/15/2023] Open
Abstract
The domestication of wild vicuña and guanaco by early pre-Inca cultures is an iconic example of wildlife management and domestication in the Americas. Although domestic llamas and alpacas were clearly selected for key, yet distinct, phenotypic traits, the relative patterns and direction of selection and domestication have not been confirmed using genetic approaches. However, the detailed archaeological records from the region suggest that domestication was a process carried out under significant control and planning, which would have facilitated coordinated and thus extremely effective selective pressure to achieve and maintain desired phenotypic traits. Here we link patterns of sequence variation in two well-characterised genes coding for colour variation in vertebrates and interpret the results in the context of domestication in guanacos and vicuñas. We hypothesise that colour variation in wild populations of guanacos and vicunas were strongly selected against. In contrast, variation in coat colour variation in alpaca was strongly selected for and became rapidly fixed in alpacas. In contrast, coat colour variants in llamas were of less economic value, and thus were under less selective pressure. We report for the first time the full sequence of MC1R and 3 exons of ASIP in 171 wild specimens from throughout their distribution and which represented a range of commonly observed colour patterns. We found a significant difference in the number of non-synonymous substitutions, but not synonymous substitutions among wild and domestics species. The genetic variation in MC1R and ASIP did not differentiate alpaca from llama due to the high degree of reciprocal introgression, but the combination of 11 substitutions are sufficient to distinguish domestic from wild animals. Although there is gene flow among domestic and wild species, most of the non-synonymous variation in MC1R and ASIP was not observed in wild species, presumably because these substitutions and the associated colour phenotypes are not effectively transmitted back into wild populations. Therefore, this set of substitutions unequivocally differentiates wild from domestic animals, which will have important practical application in forensic cases involving the poaching of wild vicuñas and guanacos. These markers will also assist in identifying and studying archaeological remains pre- and post-domestication.
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Affiliation(s)
- Juan C. Marín
- Laboratorio de Genómica y Biodiversidad, Departamento de Ciencias Básicas, Universidad del Bío-Bío, Chillán, Chile
| | - Romina Rivera
- Laboratorio de Genómica y Biodiversidad, Departamento de Ciencias Básicas, Universidad del Bío-Bío, Chillán, Chile
- Departamento de Ciencias Básicas, Universidad Santo Tomas, Iquique, Chile
| | - Valeria Varas
- Doctorado en Ciencias, Mención Ecología y Evolución, Instituto de Ciencias Ambientales & Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Jorge Cortés
- Laboratorio de Genómica y Biodiversidad, Departamento de Ciencias Básicas, Universidad del Bío-Bío, Chillán, Chile
- Departamento de Zoología, Universidad de Concepción, Concepción, Chile
| | - Ana Agapito
- Laboratorio de Genómica y Biodiversidad, Departamento de Ciencias Básicas, Universidad del Bío-Bío, Chillán, Chile
| | - Ana Chero
- Laboratorio de Genómica y Biodiversidad, Departamento de Ciencias Básicas, Universidad del Bío-Bío, Chillán, Chile
| | - Alexandra Chávez
- Laboratorio de Genómica y Biodiversidad, Departamento de Ciencias Básicas, Universidad del Bío-Bío, Chillán, Chile
| | - Warren E. Johnson
- Smithsonian Conservation Biology Institute, Smithsonian Institution, Washington, DC, United States
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10
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Stamatis C, Giannoulis T, Galliopoulou E, Billinis C, Mamuris Z. Genetic analysis of melanocortin 1 receptor gene in endangered Greek sheep breeds. Small Rumin Res 2017. [DOI: 10.1016/j.smallrumres.2017.09.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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11
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Polymorphisms in MC1R and ASIP genes and their association with coat color phenotypes in llamas (Lama glama). Small Rumin Res 2016. [DOI: 10.1016/j.smallrumres.2016.08.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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12
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Wang X, Niu Y, Zhou J, Yu H, Kou Q, Lei A, Zhao X, Yan H, Cai B, Shen Q, Zhou S, Zhu H, Zhou G, Niu W, Hua J, Jiang Y, Huang X, Ma B, Chen Y. Multiplex gene editing via CRISPR/Cas9 exhibits desirable muscle hypertrophy without detectable off-target effects in sheep. Sci Rep 2016; 6:32271. [PMID: 27562433 PMCID: PMC4999810 DOI: 10.1038/srep32271] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 08/04/2016] [Indexed: 01/20/2023] Open
Abstract
The CRISPR/Cas9 system provides a flexible approach for genome engineering of genetic loci. Here, we successfully achieved precise gene targeting in sheep by co-injecting one-cell-stage embryos with Cas9 mRNA and RNA guides targeting three genes (MSTN, ASIP, and BCO2). We carefully examined the sgRNAs:Cas9-mediated targeting effects in injected embryos, somatic tissues, as well as gonads via cloning and sequencing. The targeting efficiencies in these three genes were within the range of 27–33% in generated lambs, and that of simultaneously targeting the three genes was 5.6%, which demonstrated that micro-injection of zygotes is an efficient approach for generating gene-modified sheep. Interestingly, we observed that disruption of the MSTN gene resulted in the desired muscle hypertrophy that is characterized by enlarged myofibers, thereby providing the first detailed evidence supporting that gene modifications had occurred at both the genetic and morphological levels. In addition, prescreening for the off-target effect of sgRNAs was performed on fibroblasts before microinjection, to ensure that no detectable off-target mutations from founder animals existed. Our findings suggested that the CRISPR/Cas9 method can be exploited as a powerful tool for livestock improvement by simultaneously targeting multiple genes that are responsible for economically significant traits.
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Affiliation(s)
- Xiaolong Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling 712100, China
| | - Yiyuan Niu
- College of Animal Science and Technology, Northwest A&F University, Yangling 712100, China
| | - Jiankui Zhou
- MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center of Nanjing University, National Resource Center for Mutant Mice, Nanjing 210061, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Honghao Yu
- College of Life Science, Yulin University, Yulin 719000, China
| | - Qifang Kou
- Ningxia Tianyuan Sheep Farm, Hongsibu, 751999, China
| | - Anmin Lei
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Xiaoe Zhao
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Hailong Yan
- College of Animal Science and Technology, Northwest A&F University, Yangling 712100, China.,College of Life Science, Yulin University, Yulin 719000, China
| | - Bei Cai
- College of Animal Science and Technology, Northwest A&F University, Yangling 712100, China
| | - Qiaoyan Shen
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Shiwei Zhou
- College of Animal Science and Technology, Northwest A&F University, Yangling 712100, China
| | - Haijing Zhu
- College of Life Science, Yulin University, Yulin 719000, China
| | - Guangxian Zhou
- College of Animal Science and Technology, Northwest A&F University, Yangling 712100, China
| | - Wenzhi Niu
- Ningxia Tianyuan Sheep Farm, Hongsibu, 751999, China
| | - Jinlian Hua
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Yu Jiang
- College of Animal Science and Technology, Northwest A&F University, Yangling 712100, China
| | - Xingxu Huang
- MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center of Nanjing University, National Resource Center for Mutant Mice, Nanjing 210061, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Baohua Ma
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Yulin Chen
- College of Animal Science and Technology, Northwest A&F University, Yangling 712100, China
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13
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Mahmoud AH, Mashaly AM, Rady AM, Al-Anazi KM, Saleh AA. Allelic variation of melanocortin-1 receptor locus in Saudi indigenous sheep exhibiting different color coats. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2016; 30:154-159. [PMID: 27492350 PMCID: PMC5205600 DOI: 10.5713/ajas.16.0138] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 05/21/2016] [Accepted: 08/01/2016] [Indexed: 11/27/2022]
Abstract
Objective This study was designed to characterize the DNA polymorphisms of the melanocortin-1 receptor (MC1R) gene in indigenous Saudi Arabian sheep breeds exhibiting different color coats, along with individuals of the Sawaknee breed, an exotic sheep imported from Sudan. Methods The complete coding region of MC1R gene including parts of 3′ and 5′ untranslated regions was amplified and sequenced from three the indigenous Saudi sheep; Najdi (generally black, n = 41), Naeimi (generally white with brown faces, n = 36) and Herri (generally white, n = 18), in addition to 13 Sawaknee sheep. Results Five single nucleotide polymorphisms (SNPs) were detected in the MC1R gene: two led to nonsynonymous mutations (c.218 T>A, p.73 Met>Lys and c.361 G>A, p.121 Asp>Asn) and three led to synonymous mutations (c.429 C>T, p.143 Tyr>Tyr; c.600 T>G, p.200 Leu>Leu, and c.735 C>T, p.245 Ile>Ile). Based on these five SNPs, eight haplotypes representing MC1R Ed and E+ alleles were identified among the studied sheep breeds. The most common haplotype (H3) of the dominant Ed allele was associated with either black or brown coat color in Najdi and Sawaknee sheep, respectively. Two other haplotypes (H6 and H7) of Ed allele, with only the nonsynonymous mutation A218T, were detected for the first time in Saudi indigenous sheep. Conclusion In addition to investigating the MC1R allelic variation in Saudi indigenous sheep populations, the present study supports the assumption that the two independent nonsynonymous Met73Lys and Asp121Asn mutations in MC1R gene are associated with black or red coat colors in sheep breeds.
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Affiliation(s)
- Ahmed H Mahmoud
- Zoology Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ashraf M Mashaly
- Zoology Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ahmed M Rady
- Zoology Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Khalid M Al-Anazi
- Zoology Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Amgad A Saleh
- Department of Plant Protection, College of Food and Agricultural Sciences, King Saud University, Riyadh 11451, Saudi Arabia.,Agricultural Genetic Engineering Research Institute (AGERI), Agriculture Research Center (ARC), Giza 12619, Egypt
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14
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Hepp D, Gonçalves GL, Moreira GRP, de Freitas TRO. Epistatic Interaction of the Melanocortin 1 Receptor and Agouti Signaling Protein Genes Modulates Wool Color in the Brazilian Creole Sheep. J Hered 2016; 107:544-52. [PMID: 27288530 DOI: 10.1093/jhered/esw037] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Accepted: 05/29/2016] [Indexed: 02/01/2023] Open
Abstract
Different pigmentation genes have been associated with color diversity in domestic animal species. The melanocortin 1 receptor (MC1R), agouti signaling protein (ASIP), tyrosinase-related protein 1 (TYRP1), and v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog (KIT) genes are candidate genes responsible for variation in wool color among breeds of sheep. Although the influence of these genes has been described in some breeds, in many others the effect of interactions among genes underlying wool color has not been investigated. The Brazilian Creole sheep is a local breed with a wide variety of wool color, ranging from black to white with several intermediate hues. We analyzed in this study the influence of the genes MC1R, ASIP, TYRP1, and KIT on the control of wool color in this breed. A total of 410 samples were analyzed, including 148 white and 262 colored individuals. The MC1R and ASIP polymorphisms were significantly associated with the segregation of either white or colored wool. The dominant MC1R allele (E(D) p.M73K and p.D121N) was present only in colored animals. All white individuals were homozygous for the MC1R recessive allele (E(+)) and carriers of the duplicated copy of ASIP A gene expression assay showed that only the carrier of the duplicated copy of ASIP produces increased levels in skin, not detectable in the single homozygous copy. These results demonstrate that the epistatic interaction of the genotypes in the MC1R and ASIP gene is responsible for the striking color variation in the Creole breed.
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Affiliation(s)
- Diego Hepp
- From the Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Hepp, Gonçalves, and de Freitas); Instituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile (Gonçalves); Departamento de Zoologia, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Moreira); and Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Hepp).
| | - Gislene Lopes Gonçalves
- From the Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Hepp, Gonçalves, and de Freitas); Instituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile (Gonçalves); Departamento de Zoologia, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Moreira); and Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Hepp)
| | - Gilson Rudinei Pires Moreira
- From the Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Hepp, Gonçalves, and de Freitas); Instituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile (Gonçalves); Departamento de Zoologia, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Moreira); and Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Hepp)
| | - Thales Renato Ochotorena de Freitas
- From the Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Hepp, Gonçalves, and de Freitas); Instituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile (Gonçalves); Departamento de Zoologia, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Moreira); and Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil (Hepp)
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15
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Abitbol M, Legrand R, Tiret L. A missense mutation in the agouti signaling protein gene (ASIP) is associated with the no light points coat phenotype in donkeys. Genet Sel Evol 2015; 47:28. [PMID: 25887951 PMCID: PMC4389795 DOI: 10.1186/s12711-015-0112-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 03/18/2015] [Indexed: 11/23/2022] Open
Abstract
Background Seven donkey breeds are recognized by the French studbook and are characterized by a black, bay or grey coat colour including light cream-to-white points (LP). Occasionally, Normand bay donkeys give birth to dark foals that lack LP and display the no light points (NLP) pattern. This pattern is more frequent and officially recognized in American miniature donkeys. The LP (or pangare) phenotype resembles that of the light bellied agouti pattern in mouse, while the NLP pattern resembles that of the mammalian recessive black phenotype; both phenotypes are associated with the agouti signaling protein gene (ASIP). Findings We used a panel of 127 donkeys to identify a recessive missense c.349 T > C variant in ASIP that was shown to be in complete association with the NLP phenotype. This variant results in a cysteine to arginine substitution at position 117 in the ASIP protein. This cysteine is highly-conserved among vertebrate ASIP proteins and was previously shown by mutagenesis experiments to lie within a functional site. Altogether, our results strongly support that the identified mutation is causative of the NLP phenotype. Conclusions Thus, we propose to name the c.[349 T > C] allele in donkeys, the anlp allele, which enlarges the panel of coat colour alleles in donkeys and ASIP recessive loss-of-function alleles in animals. Electronic supplementary material The online version of this article (doi:10.1186/s12711-015-0112-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Marie Abitbol
- Inra, Unité de Génétique Fonctionnelle et Médicale, Ecole nationale vétérinaire d'Alfort, Maisons-Alfort, 94700, France. .,Inserm, U955 IMRB, Equipe 10, Université Paris-Est, Créteil, 94000, France.
| | - Romain Legrand
- Inra, Unité de Génétique Fonctionnelle et Médicale, Ecole nationale vétérinaire d'Alfort, Maisons-Alfort, 94700, France. .,Inserm, U955 IMRB, Equipe 10, Université Paris-Est, Créteil, 94000, France.
| | - Laurent Tiret
- Inra, Unité de Génétique Fonctionnelle et Médicale, Ecole nationale vétérinaire d'Alfort, Maisons-Alfort, 94700, France. .,Inserm, U955 IMRB, Equipe 10, Université Paris-Est, Créteil, 94000, France.
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16
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Mutations in MC1R gene determine black coat color phenotype in Chinese sheep. ScientificWorldJournal 2013; 2013:675382. [PMID: 24082855 PMCID: PMC3776380 DOI: 10.1155/2013/675382] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2013] [Accepted: 07/26/2013] [Indexed: 11/24/2022] Open
Abstract
The melanocortin receptor 1 (MC1R) plays a central role in regulation of animal coat color formation. In this study, we sequenced the complete coding region
and parts of the 5′- and 3′-untranslated regions of the MC1R gene in Chinese sheep with completely
white (Large-tailed Han sheep), black (Minxian Black-fur sheep), and brown coat colors (Kazakh Fat-Rumped sheep). The results showed five single nucleotide
polymorphisms (SNPs): two non-synonymous mutations previously associated with coat color (c.218 T>A, p.73 Met>Lys. c.361 G>A, p.121 Asp>Asn)
and three synonymous mutations (c.429 C>T, p.143 Tyr>Tyr; c.600 T>G, p.200 Leu>Leu. c.735 C>T, p.245 Ile>Ile). Meanwhile, all mutations
were detected in Minxian Black-fur sheep. However, the two nonsynonymous mutation sites were not in all studied breeds (Large-tailed Han, Small-tailed Han, Gansu Alpine Merino,
and China Merino breeds), all of which are in white coat. A single haplotype AATGT (haplotype3) was uniquely associated with black coat color in Minxian Black-fur breed (P = 9.72E − 72, chi-square test). The first and second A alleles in this haplotype 3 represent location at 218 and 361 positions, respectively. Our results suggest that the mutations
of MC1R gene are associated with black coat color phenotype in Chinese sheep.
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17
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Identification of single nucleotide polymorphisms in the agouti signaling protein (ASIP) gene in some goat breeds in tropical and temperate climates. Mol Biol Rep 2013; 40:4447-57. [PMID: 23661018 DOI: 10.1007/s11033-013-2535-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Accepted: 04/29/2013] [Indexed: 10/26/2022]
Abstract
The agouti-signaling protein (ASIP) plays a major role in mammalian pigmentation as an antagonist to melanocortin-1 receptor gene to stimulate pheomelanin synthesis, a major pigment conferring mammalian coat color. We sequenced a 352 bp fragment of ASIP gene spanning part of exon 2 and part of intron 2 in 215 animals representing six goat breeds from Nigeria and the United States: West African Dwarf, predominantly black; Red Sokoto, mostly red; and Sahel, mostly white from Nigeria; black and white Alpine, brown and white Spanish and white Saanen from the US. Twenty haplotypes from nine mutations representing three intronic, one silent and five missense (p.S19R, p.N35K, p.L36V, p.M42L and p.L45W) mutations were identified in Nigerian goats. Approximately 89 % of Nigerian goats carry haplotype 1 (TGCCATCCG) which seems to be the wild type configuration of mutations in this region of the gene. Although we found no association between these polymorphisms in the ASIP gene and coat color in Nigerian goats, in-silico functional analysis predicts putative deleterious functional impact of the p.L45W mutation on the basic amino-terminal domain of ASIP. In the American goats, two intronic mutations, g.293G>A and g.327C>A, were identified in the Alpine breed, although the g.293G>A mutation is common to American and Nigerian goat populations. All Sannen and Sahel goats in this study belong to haplotypes 1 of both populations which seem to be the wild-type composite ASIP haplotype. Overall, there was no clear association of this portion of the ASIP gene interrogated in this study with coat color variation. Therefore, additional genomic analyses of promoter sequence, the entire coding and non-coding regions of the ASIP gene will be required to obtain a definite conclusion.
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18
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Dreger DL, Parker HG, Ostrander EA, Schmutz SM. Identification of a mutation that is associated with the saddle tan and black-and-tan phenotypes in Basset Hounds and Pembroke Welsh Corgis. ACTA ACUST UNITED AC 2013; 104:399-406. [PMID: 23519866 DOI: 10.1093/jhered/est012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The causative mutation for the black-and-tan (a (t) ) phenotype in dogs was previously shown to be a SINE insertion in the 5' region of Agouti Signaling Protein (ASIP). Dogs with the black-and-tan phenotype, as well as dogs with the saddle tan phenotype, genotype as a (t) /_ at this locus. We have identified a 16-bp duplication (g.1875_1890dupCCCCAGGTCAGAGTTT) in an intron of hnRNP associated with lethal yellow (RALY), which segregates with the black-and-tan phenotype in a group of 99 saddle tan and black-and-tan Basset Hounds and Pembroke Welsh Corgis. In these breeds, all dogs with the saddle tan phenotype had RALY genotypes of +/+ or +/dup, whereas dogs with the black-and-tan phenotype were homozygous for the duplication. The presence of an a (y) /_ fawn or e/e red genotype is epistatic to the +/_ saddle tan genotype. Genotypes from 10 wolves and 1 coyote indicated that the saddle tan (+) allele is the ancestral allele, suggesting that black-and-tan is a modification of saddle tan. An additional 95 dogs from breeds that never have the saddle tan phenotype have all three of the possible RALY genotypes. We suggest that a multi-gene interaction involving ASIP, RALY, MC1R, DEFB103, and a yet-unidentified modifier gene is required for expression of saddle tan.
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Affiliation(s)
- Dayna L Dreger
- Department of Animal and Poultry Science, University of Saskatchewan, 51 Campus Dr., Saskatoon, SK, Canada.
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Raadsma HW, Jonas E, Fleet MR, Fullard K, Gongora J, Cavanagh CR, Tammen I, Thomson PC. QTL and association analysis for skin and fibre pigmentation in sheep provides evidence of a major causative mutation and epistatic effects. Anim Genet 2013; 44:547-59. [PMID: 23451726 DOI: 10.1111/age.12033] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/20/2013] [Indexed: 11/30/2022]
Abstract
The pursuits of white features and white fleeces free of pigmented fibre have been important selection objectives for many sheep breeds. The cause and inheritance of non-white colour patterns in sheep has been studied since the early 19th century. Discovery of genetic causes, especially those which predispose pigmentation in white sheep, may lead to more accurate selection tools for improved apparel wool. This article describes an extended QTL study for 13 skin and fibre pigmentation traits in sheep. A total of 19 highly significant, 10 significant and seven suggestive QTL were identified in a QTL mapping experiment using an Awassi × Merino × Merino backcross sheep population. All QTL on chromosome 2 exceeded a LOD score of greater than 4 (range 4.4-30.1), giving very strong support for a major gene for pigmentation on this chromosome. Evidence of epistatic interactions was found for QTL for four traits on chromosomes 2 and 19. The ovine TYRP1 gene on OAR 2 was sequenced as a strong positional candidate gene. A highly significant association (P < 0.01) of grandparental haplotypes across nine segregating SNP/microsatellite markers including one non-synonymous SNP with pigmentation traits could be shown. Up to 47% of the observed variation in pigmentation was accounted for by models using TYRP1 haplotypes and 83% for models with interactions between two QTL probabilities, offering scope for marker-assisted selection for these traits.
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Affiliation(s)
- H W Raadsma
- ReproGen-Animal Bioscience Group, Faculty of Veterinary Science, University of Sydney, Camden, NSW 2570, Australia.
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Hepp D, Gonçalves GL, Moreira GRP, Freitas TRO, Martins CTDC, Weimer TA, Passos DT. Identification of the e allele at the Extension locus (MC1R) in Brazilian Creole sheep and its role in wool color variation. GENETICS AND MOLECULAR RESEARCH 2012; 11:2997-3006. [PMID: 22653672 DOI: 10.4238/2012.may.22.5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The melanocortin 1 receptor (MC1R) gene has been described as responsible for the black color in some breeds of sheep, but little is known about its function in many colored breeds, particularly those with a wide range of pigmentation phenotypes. The Brazilian Creole is a local breed of sheep from southern Brazil that has a wide variety of wool colors. We examined the MC1R gene (Extension locus) to search for the e allele and determine its role in controlling wool color variation in this breed. One hundred and twenty-five animals, covering the most common Creole sheep phenotypes (black, brown, dark gray, light gray, and white), were sequenced to detect the mutations p.M73K and p.D121N. Besides these two mutations, three other synonymous sites (429, 600, and 725) were found. The dominant allele (E(D): p.73K, and p.121N) was found only in colored animals, whereas the recessive allele (E⁺: p.73M, and p.121D) was homozygous only in white individuals. We concluded that MC1R is involved in the control of wool color in Brazilian Creole sheep, particularly the dark phenotypes, although a second gene may be involved in the expression of the white phenotype in this breed.
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Affiliation(s)
- D Hepp
- Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brasil
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Analysis of polymorphisms in the agouti signalling protein (ASIP) and melanocortin 1 receptor (MC1R) genes and association with coat colours in two Pramenka sheep types. Small Rumin Res 2012. [DOI: 10.1016/j.smallrumres.2012.02.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Montowska M, Pospiech E. Is Authentication of Regional and Traditional Food Made of Meat Possible? Crit Rev Food Sci Nutr 2012; 52:475-87. [DOI: 10.1080/10408398.2010.501408] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Coat colours in the Massese sheep breed are associated with mutations in the agouti signalling protein (ASIP) and melanocortin 1 receptor (MC1R) genes. Animal 2012; 5:8-17. [PMID: 22440696 DOI: 10.1017/s1751731110001382] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Massese is an Italian dairy sheep breed characterized by animals with black skin and horns and black or apparent grey hairs. Owing to the presence of these two coat colour types, this breed can be considered an interesting model to evaluate the effects of coat colour gene polymorphisms on this phenotypic trait. Two main loci have been already shown to affect coat colour in sheep: Agouti and Extension coding for the agouti signalling protein (ASIP) and melanocortin 1 receptor (MC1R) genes, respectively. The Agouti locus is affected by a large duplication including the ASIP gene that may determine the Agouti white and tan allele (A(Wt)). Other disrupting or partially inactivating mutations have been identified in exon 2 (a deletion of 5 bp, D(5); and a deletion of 9 bp, D(9)) and in exon 4 (g.5172T>A, p.C126S) of the ASIP gene. Three missense mutations in the sheep MC1R gene cause the dominant black E(D) allele (p.M73K and p.D121N) and the putative recessive e allele (p.R67C). Here, we analysed these ASIP and MC1R mutations in 161 Massese sheep collected from four flocks. The presence of one duplicated copy allele including the ASIP gene was associated with grey coat colour (P = 9.4E-30). Almost all animals with a duplicated copy allele (37 out of 41) showed uniform apparent grey hair and almost all animals without a duplicated allele (117 out of 120) were completely black. Different forms of duplicated alleles were identified in Massese sheep including, in almost all cases, copies with exon 2 disrupting or partially inactivating mutations making these alleles different from the A(Wt) allele. A few exceptions were observed in the association between ASIP polymorphisms and coat colour: three grey sheep did not carry any duplicated copy allele and four black animals carried a duplicated copy allele. Of the latter four sheep, two carried the E(D) allele of the MC1R gene that may be the cause of their black coat colour. The coat colour of all other black animals may be determined by non-functional ASIP alleles (non-agouti alleles, A(a)) and in a few cases by the E(D) Extension allele. At least three frequent ASIP haplotypes ([D(5):g.5172T], [N:g.5172A] and [D(5):g.5172A]) were detected (organized into six different diplotypes). In conclusion, the results indicated that coat colours in the Massese sheep breed are mainly derived by combining ASIP and MC1R mutations.
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Dreger DL, Schmutz SM. A SINE insertion causes the black-and-tan and saddle tan phenotypes in domestic dogs. J Hered 2011; 102 Suppl 1:S11-8. [PMID: 21846741 DOI: 10.1093/jhered/esr042] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Agouti Signaling Protein (ASIP) controls the localized expression of red and black pigment in the domestic dog through interaction with other genes, such as Melanocortin 1 Receptor and Beta-Defensin 103. Specific ASIP alleles are necessary for many of the coat color patterns, such as black-and-tan and saddle tan. Mutations in 2 ASIP alleles, a(y) and a, have previously been identified. Here, we characterize a mutation consisting of a short interspersed nuclear element (SINE) insertion in intron 1 of ASIP that allows for the differentiation of the a(w) wolf sable and a(t) black-and-tan alleles. The SINE insertion is present in dogs with the a(t) and a alleles but absent from dogs with the a(w) and a(y) alleles. Dogs with the saddle tan phenotype were all a(t)/a(t). Schnauzers were all a(w)/a(w). Genotypes of 201 dogs of 35 breeds suggest that there are only 4 ASIP alleles, as opposed to the 5 or 6 predicted in previous literature. These data demonstrate that the dominance hierarchy of ASIP is a(y) > a(w) > a(t) > a.
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Affiliation(s)
- Dayna L Dreger
- Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Canada.
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Peñagaricano F, Zorrilla P, Naya H, Robello C, Urioste JI. Gene expression analysis identifies new candidate genes associated with the development of black skin spots in Corriedale sheep. J Appl Genet 2011; 53:99-106. [PMID: 21952730 DOI: 10.1007/s13353-011-0066-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Revised: 08/25/2011] [Accepted: 09/14/2011] [Indexed: 10/17/2022]
Abstract
The white coat colour of sheep is an important economic trait. For unknown reasons, some animals are born with, and others develop with time, black skin spots that can also produce pigmented fibres. The presence of pigmented fibres in the white wool significantly decreases the fibre quality. The aim of this work was to study gene expression in black spots (with and without pigmented fibres) and white skin by microarray techniques, in order to identify the possible genes involved in the development of this trait. Five unrelated Corriedale sheep were used and, for each animal, the three possible comparisons (three different hybridisations) between the three samples of interest were performed. Differential gene expression patterns were analysed using different t-test approaches. Most of the major genes with well-known roles in skin pigmentation, e.g. ASIP, MC1R and C-KIT, showed no significant difference in the gene expression between white skin and black spots. On the other hand, many of the differentially expressed genes (raw P-value < 0.005) detected in this study, e.g. C-FOS, KLF4 and UFC1, fulfil biological functions that are plausible to be involved in the formation of black spots. The gene expression of C-FOS and KLF4, transcription factors involved in the cellular response to external factors such as ultraviolet light, was validated by quantitative polymerase chain reaction (PCR). This exploratory study provides a list of candidate genes that could be associated with the development of black skin spots that should be studied in more detail. Characterisation of these genes will enable us to discern the molecular mechanisms involved in the development of this feature and, hence, increase our understanding of melanocyte biology and skin pigmentation. In sheep, understanding this phenomenon is a first step towards developing molecular tools to assist in the selection against the presence of pigmented fibres in white wool.
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Affiliation(s)
- Francisco Peñagaricano
- Departamento de Producción Animal y Pasturas, Facultad de Agronomía, Universidad de la Republica, Montevideo, Uruguay.
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Abstract
During the last decade, coat colouration in mammals has been investigated in numerous studies. Most of these studies addressing the genetics of coat colouration were on domesticated animals. In contrast to their wild ancestors, domesticated species are often characterized by a huge allelic variability of coat-colour-associated genes. This variability results from artificial selection accepting negative pleiotropic effects linked with certain coat-colour variants. Recent studies demonstrate that this selection for coat-colour phenotypes started at the beginning of domestication. Although to date more than 300 genetic loci and more than 150 identified coat-colour-associated genes have been discovered, which influence pigmentation in various ways, the genetic pathways influencing coat colouration are still only poorly described. On the one hand, similar coat colourations observed in different species can be the product of a few conserved genes. On the other hand, different genes can be responsible for highly similar coat colourations in different individuals of a species or in different species. Therefore, any phenotypic classification of coat colouration blurs underlying differences in the genetic basis of colour variants. In this review we focus on (i) the underlying causes that have resulted in the observed increase of colour variation in domesticated animals compared to their wild ancestors, and (ii) the current state of knowledge with regard to the molecular mechanisms of colouration, with a special emphasis on when and where the different coat-colour-associated genes act.
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Affiliation(s)
- Michael Cieslak
- Leibniz Institute for Zoo and Wildlife Research, Research Group of Evolutionary Genetics, Berlin, Germany
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Polymorphism of the goat agouti signaling protein gene and its relationship with coat color in Italian and Spanish breeds. Biochem Genet 2011; 49:523-32. [PMID: 21373989 DOI: 10.1007/s10528-011-9427-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Accepted: 12/15/2010] [Indexed: 10/18/2022]
Abstract
Agouti signaling protein (ASIP) is one of the key players in the modulation of hair pigmentation in mammals. Binding to the melanocortin 1 receptor, ASIP induces the synthesis of phaeomelanin, associated with reddish brown, red, tan, and yellow coats. We have sequenced 2.8 kb of the goat ASIP gene in 48 individuals and identified two missense (Cys126Gly and Val128Gly) and two intronic polymorphisms. In silico analysis revealed that the Cys126Gly substitution may cause a structural change by disrupting a highly conserved disulfide bond. We studied its segregation in 12 Spanish and Italian goat breeds (N = 360) with different pigmentation patterns and found striking differences in the frequency of the putative loss-of-function Gly(126) allele (Italian 0.43, Spanish Peninsular 0.08), but we did not observe a clear association with coat color. This suggests that the frequency of this putative loss-of-function allele has evolved under the influence of demographic rather than selection factors in goats from these two geographical areas.
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A melanocortin 1 receptor (MC1R) gene polymorphism is useful for authentication of Massese sheep dairy products. J DAIRY RES 2011; 78:122-8. [DOI: 10.1017/s0022029910000890] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Massese is an Italian sheep breed, with black or grey coat colour, mainly reared in the Tuscany and Emilia Romagna regions. Recently, the emerging interests in this breed have resulted in the production of Pecorino cheese obtained with only Massese milk. In order to be profitable, this marketing link between Massese breed and its products should be defended against fraudsters who could include milk of other sheep breeds or cow milk in Massese labelled productions. To identify the genetic factors affecting coat colour in sheep, we have recently analysed the melanocortin 1 receptor (MC1R) gene and identified several single nucleotide polymorphisms (SNPs). In this work, as a first step to set up a DNA based protocol for authentication of Massese dairy products, we further investigated the presence and distribution of one of these SNPs (c.-31G>A) in 143 Massese sheep and in another 13 sheep breeds (for a total of 351 animals). The Massese breed was fixed for allele c.-31A, whereas in all other breeds allele c.-31 G was the most frequent or with frequency of 0·50. At the same nucleotide position the cattleMC1Rgene carries the G nucleotide. Using these data we developed a method to detect adulterating milk (from other sheep breeds or from cow) in Massese dairy products based on the analysis of the c.-31G>A SNP. We first tested the sensitivity of the protocol and then applied it to analyse DNA extracted from ricotta and Pecorino cheese obtained with only Massese milk or obtained with unrestricted sheep and cattle milk. To our knowledge, this system represents the first one that can be used for breed authentication of a sheep production and that, at the same time, can reveal frauds derived from the admixture of milk of an unreported species.
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Sequence characterization of the melanocortin 1 receptor (MC1R) gene in sheep with different coat colours and identification of the putative e allele at the ovine Extension locus. Small Rumin Res 2010. [DOI: 10.1016/j.smallrumres.2010.03.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Rouzaud F, Oulmouden A, Kos L. The untranslated side of hair and skin mammalian pigmentation: Beyond coding sequences. IUBMB Life 2010; 62:340-6. [PMID: 20222017 DOI: 10.1002/iub.318] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
For several decades, tremendous advances in studying skin and hair pigmentation of mammals have been made using Mendelian genetics principles. A number of loci and their associated traits have been extensively examined, crossings performed, and phenotypes well documented. Continuously improving PCR techniques allowed the molecular cloning and sequencing of the first pigmentation genes at the end of the 20th century, a period followed by an intense effort to detect and describe polymorphisms in the coding regions and correlate allelic combinations with the observed melanogenic phenotypes. However, a number of phenotypes and biological events could not be elucidated solely by analysis of the coding regions of genes. Messenger RNA isolation, characterization and quantification techniques allowed groups to move ahead and investigate molecular mechanisms whose secrets lay within the noncoding regions of pigmentation genes transcripts such as MC1R, ASIP, or Mitf. The untranslated elements contain specific nucleotidic sequences and structures that dramatically influence the mRNA half-life and processing thus impacting protein translation and melanin production. As we are progressively uncovering the complex processes regulating melanocyte biology, unraveling complete mRNA structures and understanding mechanisms beyond coding regions has become critical.
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Affiliation(s)
- Francois Rouzaud
- Department of Biological Sciences, Florida International University, Miami, FL, USA
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Characterization of the rabbit agouti signaling protein (ASIP) gene: transcripts and phylogenetic analyses and identification of the causative mutation of the nonagouti black coat colour. Genomics 2009; 95:166-75. [PMID: 20004240 DOI: 10.1016/j.ygeno.2009.11.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2009] [Revised: 11/24/2009] [Accepted: 11/27/2009] [Indexed: 10/20/2022]
Abstract
The agouti locus encodes the agouti signalling protein (ASIP) which is involved in determining the switch from eumelanin to pheomelanin synthesis in melanocytes. In the domestic rabbit (Oryctolagus cuniculus) early studies indicated three alleles at this locus: A, light-bellied agouti (wild type); a(t), black and tan; a, black nonagouti. We characterized the rabbit ASIP gene and identified the causative mutation (an insertion in exon 2) of the black nonagouti allele whose frequency was evaluated in 31 breeds. Phylogenetic analysis of ASIP sequences from Oryctolagus and 9 other species of the family Leporidae placed Oryctolagus as sister species to Pentalagus and Bunolagus. Transcription analysis in wild type agouti rabbits revealed the presence of two major transcripts with different 5'-untranslated regions having ventral or dorsal skin specific expression. ASIP gene transcripts were also detected in all examined rabbit tissues distinguishing the rabbit expression pattern from what was observed in wild type mice.
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The genetic basis of recessive self-colour pattern in a wild sheep population. Heredity (Edinb) 2009; 104:206-14. [PMID: 19672282 DOI: 10.1038/hdy.2009.105] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Bridging the genotype-phenotype gap for traits of ecological and evolutionary importance in natural populations can provide a novel insight into the origin and maintenance of variation. Here, we identify the gene and putative causal mutations underlying a recessive colour pattern phenotype ('self' or uniform colour) in a wild population of primitive Soay sheep. We targeted the agouti signalling protein (ASIP) gene, a positional candidate based on previous study that mapped the Coat pattern locus to a presumptive region on chromosome 13. We found evidence for three recessive mutations, including two functional changes in the coding sequence and a putative third cis-regulatory mutation that inactivates the promoter. These mutations define up to five haplotypes in Soays, which collectively explained the coat pattern in all but one member of a complex multi-generational pedigree containing 621 genotyped individuals. The functional mutations are in strong linkage disequilibrium in the study population, and are identical to those known to underlie the self phenotype in domestic sheep. This is indicative of a recent (and simultaneous) origin in Soay sheep, possibly as a consequence of past interbreeding with modern domestic breeds. This is only the second study in which ASIP has been linked to variation in pigmentation in a natural population. Knowledge of the genetic basis of self-colour pattern in Soay sheep, and the recognition that several mutations are segregating in the population, will aid future studies investigating the role of selection in the maintenance of the polymorphism.
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