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Doi H, Kageyama I, Katoh-Fukui Y, Hattori A, Fukami M, Shimura N. Homozygous 6-bp deletion of IGFALS in a prepubertal boy with short stature. Hum Genome Var 2024; 11:27. [PMID: 39060265 PMCID: PMC11282113 DOI: 10.1038/s41439-024-00285-w] [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: 05/28/2024] [Revised: 06/24/2024] [Accepted: 06/25/2024] [Indexed: 07/28/2024] Open
Abstract
Biallelic IGFALS variants lead to acid‒labile subunit (ALS) deficiency characterized by growth hormone resistance with or without delayed puberty. Here, we report a prepubertal boy with a homozygous 2-amino acid deletion within the fourth N-glycosylation motif (c.1103_1108del, p.N368_S370delinsT) associated with parental consanguinity. He showed short stature consistent with ALS deficiency. This case expands the mutation spectrum of IGFALS to include the elimination of only one N-glycosylation motif of ALS.
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Affiliation(s)
- Hibiki Doi
- Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan
- Department of Advanced Pediatric Medicine, Tohoku University School of Medicine, Tokyo, Japan
| | - Ikuko Kageyama
- Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Yuko Katoh-Fukui
- Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Atsushi Hattori
- Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Maki Fukami
- Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan.
| | - Naoto Shimura
- Department of Pediatrics, Tokyo Rinkai Hospital, Tokyo, Japan
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2
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Singh A, Pajni K, Panigrahi I, Dhoat N, Senapati S, Khetarpal P. Components of IGF-axis in growth disorders: a systematic review and patent landscape report. Endocrine 2022; 76:509-525. [PMID: 35523998 DOI: 10.1007/s12020-022-03063-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 04/20/2022] [Indexed: 11/03/2022]
Abstract
PURPOSE In this review, epi/genetic mutations of IGF-axis components associated with growth disorders have been summarized alongwith assessment of relevant diagnostic and therapeutic technology through patent literature. METHODOLOGY PROSPERO protocol registration CRD42021279468. For scientific literature search Literature databases (PubMed, EMBASE, ScienceDirect, and Google Scholar) were queried using the appropriate syntax. Various filters were applied based on inclusion and exclusion criteria. Search results were further refined by two authors for finalizing studies to be included in this synthesis. For patent documents search Patent databases (Patentscope and Espacenet) were queried using keywords: IGF or IGFBP. Filters were applied according to International Patent Classification (IPC) and Cooperative Patent Classification (CPC). Search results were reviewed by two authors for inclusion in the patent landscape report. RESULTS For scientific literature analysis, out of 545 search results, 196 were selected for review based on the inclusion criteria. For Patent literature search, out of 485 results, 37 were selected for this synthesis. CONCLUSION Dysregulation of IGF-axis components leads to various abnormalities and their key role in growth and development suggests epi/mutations or structural defects among IGF-axis genes can be associated with growth disorders and may explain some of the idiopathic short stature cases. Trend of patent filings indicate advent of recombinant technology for therapeutics.
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Affiliation(s)
- Amit Singh
- Laboratory for Reproductive and Developmental Disorders, Department of Human Genetics and Molecular Medicine, School of Health Sciences, Central University of Punjab, Bathinda, 151401, India
| | - Ketan Pajni
- Department of Human Genetics and Molecular Medicine, School of Health Sciences, Central University of Punjab, Bathinda, 151401, India
| | - Inusha Panigrahi
- Department of Paediatric Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh, 160012, India
| | - Navdeep Dhoat
- Department of Paediatric Surgery, All India Institute of Medical Sciences, Bathinda, 151001, India
| | - Sabyasachi Senapati
- Department of Human Genetics and Molecular Medicine, School of Health Sciences, Central University of Punjab, Bathinda, 151401, India
| | - Preeti Khetarpal
- Laboratory for Reproductive and Developmental Disorders, Department of Human Genetics and Molecular Medicine, School of Health Sciences, Central University of Punjab, Bathinda, 151401, India.
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Domené S, Domené HM. The role of acid-labile subunit (ALS) in the modulation of GH-IGF-I action. Mol Cell Endocrinol 2020; 518:111006. [PMID: 32861700 DOI: 10.1016/j.mce.2020.111006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 08/20/2020] [Accepted: 08/24/2020] [Indexed: 12/17/2022]
Abstract
Acid-labile subunit (ALS) deficiency (ACLSD) constitutes the first monogenic defect involving a member of the Insulin-like Growth Factor (IGF) binding protein system. The lack of ALS completely disrupts the circulating IGF system. Autocrine/paracrine action of local produced IGF-I could explain the mild effect on growth. In the present work we have revised the more relevant clinical and biochemical consequences of complete ACLSD in 61 reported subjects from 31 families. Low birth weight and/or length, reduced head circumference, height between -2 and -3 SD, pubertal delay and insulin resistance are commonly observed. Partial ACLSD could be present in children initially labeled as idiopathic short stature, presenting low IGF-I levels, suggesting that one functional IGFALS allele is insufficient to stabilize ternary complexes. Dysfunction of the GH-IGF axis observed in ACLSD may eventually result in increased risk for type-2 diabetes and tumor progression. Consequently, long term surveillance is recommended in these patients.
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Affiliation(s)
- Sabina Domené
- Centro de Investigaciones Endocrinológicas 'Dr César Bergadá', (CEDIE) CONICET, FEI, División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, Buenos Aires, Argentina
| | - Horacio M Domené
- Centro de Investigaciones Endocrinológicas 'Dr César Bergadá', (CEDIE) CONICET, FEI, División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, Buenos Aires, Argentina.
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Landi E, Karabatas L, Scaglia P, Pisciottano F, Gutiérrez M, Ramírez L, Bergadá I, Rey RA, Jasper HG, Domené HM, Plazas PV, Domené S. Expression of acid-labile subunit (ALS) in developing and adult zebrafish and its role in dorso-ventral patterning during development. Gen Comp Endocrinol 2020; 299:113591. [PMID: 32828812 DOI: 10.1016/j.ygcen.2020.113591] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 07/28/2020] [Accepted: 08/18/2020] [Indexed: 11/24/2022]
Abstract
Mammalian acid-labile subunit (ALS) is a serum protein that binds binary complexes between Insulin-like growth factors (IGFs) and Insulin-like growth factor-binding proteins (IGFBPs) extending their half-life and keeping them in the vasculature. Human ALS deficiency (ACLSD), due to homozygous or compound heterozygous mutations in IGFALS, leads to moderate short stature with reduced levels of IGF-I and IGFBP-3. There is only one corresponding zebrafish ortholog gene and it has not yet been studied. In this study we elucidate the role of igfals during zebrafish development. In zebrafish embryos igfals mRNA is expressed throughout development, mainly in the brain and subsequently also in the gut and swimbladder. To determine its role during development, we knocked down igfals gene product using morpholinos (MOs). Igfals morphant embryos displayed dorsalization in different degrees of severity, including a shortened trunk and loss of tail. Furthermore, co-injection of human IGFALS (hIGFALS) mRNA was able to rescue the MO-induced phenotype. Finally, overexpression of either hIGFALS or zebrafish igfals (zigfals) mRNA leads to ventralization of embryos including a reduced head and enlarged tail. These findings suggest that als plays an important role in dorso-ventral patterning during zebrafish development.
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Affiliation(s)
- Estefanía Landi
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET-FEI-División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, C1425EFD Buenos Aires, Argentina.
| | - Liliana Karabatas
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET-FEI-División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, C1425EFD Buenos Aires, Argentina.
| | - Paula Scaglia
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET-FEI-División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, C1425EFD Buenos Aires, Argentina.
| | - Francisco Pisciottano
- Instituto de Biología y Medicina Experimental (IBYME), Vuelta de Obligado 2490, C1428ADN Buenos Aires, Argentina.
| | - Mariana Gutiérrez
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET-FEI-División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, C1425EFD Buenos Aires, Argentina.
| | - Laura Ramírez
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET-FEI-División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, C1425EFD Buenos Aires, Argentina.
| | - Ignacio Bergadá
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET-FEI-División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, C1425EFD Buenos Aires, Argentina.
| | - Rodolfo A Rey
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET-FEI-División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, C1425EFD Buenos Aires, Argentina.
| | - Héctor Guillermo Jasper
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET-FEI-División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, C1425EFD Buenos Aires, Argentina.
| | - Horacio Mario Domené
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET-FEI-División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, C1425EFD Buenos Aires, Argentina.
| | - Paola Viviana Plazas
- Instituto de Farmacología, Facultad de Medicina, Universidad de Buenos Aires (UBA), Paraguay 2155, C1121ABG Buenos Aires, Argentina.
| | - Sabina Domené
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET-FEI-División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, C1425EFD Buenos Aires, Argentina.
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5
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Poyrazoğlu Ş, Hwa V, Baş F, Dauber A, Rosenfeld R, Darendeliler F. A Novel Homozygous Mutation of the Acid-Labile Subunit (IGFALS) Gene in a Male Adolescent. J Clin Res Pediatr Endocrinol 2019; 11:432-438. [PMID: 30717585 PMCID: PMC6878349 DOI: 10.4274/jcrpe.galenos.2019.2018.0301] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Acid-labile subunit (ALS) forms ternary complexes with insulin like growth factor-1 (IGF-1) and IGF-binding protein-3 (IGFBP-3) and is essential for normal circulating IGF-1 levels. The IGFALS gene encodes the ALS and mutations in IGFALS cause ALS deficiency. We describe a patient with ALS deficiency with a novel homozygous frameshift mutation in IGFALS presenting with short stature and delayed puberty but ultimately achieving an adult height (AH) comparable to his target height (TH). A 15.25 year old boy presented with short stature (149.9 cm, -3.04 standard deviation score). The patient had a low circulating IGF-1 concentration, extremely low IGFBP-3 concentration, insulin resistance and osteopenia. The peak growth hormone (GH) response to GH stimulation test was high (31.6 ng/mL). Sequencing of IGFALS revealed a novel, homozygous, frameshift mutation (p.Ser555Thrfs.19). His mother and elder sister were heterozygous carriers. Although he had delayed puberty and short stature at the onset of puberty, he reached his TH and an AH similar to those of his heterozygous mother and sister. The heterozygous carriers had normal or low IGF-1 concentrations and low IGFBP-3 concentrations but not as markedly low as that of the patient. They had normally timed puberty, insulin metabolism and bone mineral density (BMD). The phenotype of ALS deficiency is quite variable. Despite short stature and delayed puberty, patients can achieve normal pubertal growth and AH. ALS deficiency may cause osteopenia and hyperinsulinemia. Heterozygous carriers may have normal prenatal growth, puberty, insulin metabolism and BMD.
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Affiliation(s)
- Şükran Poyrazoğlu
- İstanbul University İstanbul Faculty of Medicine, Unit of Pediatric Endocrinology, İstanbul, Turkey,* Address for Correspondence: İstanbul University İstanbul Faculty of Medicine, Unit of Pediatric Endocrinology, İstanbul, Turkey Phone: +90 212 414 20 00 E-mail:
| | - Vivian Hwa
- Cincinnati Children’s Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati Center for Growth Disorders, Cincinnati, Division of Endocrinology, Ohio, USA
| | - Firdevs Baş
- İstanbul University İstanbul Faculty of Medicine, Unit of Pediatric Endocrinology, İstanbul, Turkey
| | - Andrew Dauber
- Children’s National Healthy System, Division of Endocrinology, Washington, USA
| | - Ron Rosenfeld
- Cincinnati Children’s Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati Center for Growth Disorders, Cincinnati, Division of Endocrinology, Ohio, USA
| | - Feyza Darendeliler
- İstanbul University İstanbul Faculty of Medicine, Unit of Pediatric Endocrinology, İstanbul, Turkey
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Matsushima N, Takatsuka S, Miyashita H, Kretsinger RH. Leucine Rich Repeat Proteins: Sequences, Mutations, Structures and Diseases. Protein Pept Lett 2019; 26:108-131. [PMID: 30526451 DOI: 10.2174/0929866526666181208170027] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 11/26/2018] [Accepted: 11/26/2018] [Indexed: 12/18/2022]
Abstract
Mutations in the genes encoding Leucine Rich Repeat (LRR) containing proteins are associated with over sixty human diseases; these include high myopia, mitochondrial encephalomyopathy, and Crohn's disease. These mutations occur frequently within the LRR domains and within the regions that shield the hydrophobic core of the LRR domain. The amino acid sequences of fifty-five LRR proteins have been published. They include Nod-Like Receptors (NLRs) such as NLRP1, NLRP3, NLRP14, and Nod-2, Small Leucine Rich Repeat Proteoglycans (SLRPs) such as keratocan, lumican, fibromodulin, PRELP, biglycan, and nyctalopin, and F-box/LRR-repeat proteins such as FBXL2, FBXL4, and FBXL12. For example, 363 missense mutations have been identified. Replacement of arginine, proline, or cysteine by another amino acid, or the reverse, is frequently observed. The diverse effects of the mutations are discussed based on the known structures of LRR proteins. These mutations influence protein folding, aggregation, oligomerization, stability, protein-ligand interactions, disulfide bond formation, and glycosylation. Most of the mutations cause loss of function and a few, gain of function.
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Affiliation(s)
- Norio Matsushima
- Center for Medical Education, Sapporo Medical University, Sapporo 060-8556, Japan.,Institute of Tandem Repeats, Noboribetsu 059-0464, Japan
| | - Shintaro Takatsuka
- Center for Medical Education, Sapporo Medical University, Sapporo 060-8556, Japan
| | - Hiroki Miyashita
- Institute of Tandem Repeats, Noboribetsu 059-0464, Japan.,Hokubu Rinsho Co., Ltd, Sapporo 060-0061, Japan
| | - Robert H Kretsinger
- Department of Biology, University of Virginia, Charlottesville, VA 22904, United States
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7
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Shapiro L, Chatterjee S, Ramadan DG, Davies KM, Savage MO, Metherell LA, Storr HL. Whole-exome sequencing gives additional benefits compared to candidate gene sequencing in the molecular diagnosis of children with growth hormone or IGF-1 insensitivity. Eur J Endocrinol 2017; 177:485-501. [PMID: 28870985 DOI: 10.1530/eje-17-0453] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 08/29/2017] [Accepted: 09/04/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND GH insensitivity (GHI) is characterised by short stature, IGF-1 deficiency and normal/elevated serum GH. IGF-1 insensitivity results in pre- and post-natal growth failure with normal/high IGF-1 levels. The prevalence of genetic defects is unknown. OBJECTIVE To identify the underlying genetic diagnoses in a paediatric cohort with GH or IGF-1 insensitivity using candidate gene (CGS) and whole-exome sequencing (WES) and assess factors associated with the discovery of a genetic defect. METHODS We undertook a prospective study of 132 patients with short stature and suspected GH or IGF-1 insensitivity referred to our centre for genetic analysis. 107 (96 GHI, 88 probands; 11 IGF-1 insensitivity, 9 probands) underwent CGS. WES was performed in those with no defined genetic aetiology following CGS. RESULTS A genetic diagnosis was discovered 38/107 (36%) patients (32% probands) by CGS. WES revealed 11 patients with genetic variants in genes known to cause short stature. A further 2 patients had hypomethylation in the H19/IGF2 region or mUPD7 consistent with Silver-Russell Syndrome (total with genetic diagnosis 51/107, 48% or 41/97, 42% probands). WES also identified homozygous putative variants in FANCA and PHKB in 2 patients. Low height SDS and consanguinity were highly predictive for identifying a genetic defect. CONCLUSIONS Comprehensive genetic testing confirms the genetic heterogeneity of GH/IGF-1 insensitivity and successfully identified the genetic aetiology in a significant proportion of cases. WES is rapid and may isolate genetic variants that have been missed by traditional clinically driven genetic testing. This emphasises the benefits of specialist diagnostic centres.
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Affiliation(s)
- Lucy Shapiro
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Sumana Chatterjee
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Dina G Ramadan
- Department of Pediatrics and Endocrinology Unit, Sabah Hospital, Safat, Kuwait
| | - Kate M Davies
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Martin O Savage
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Louise A Metherell
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Helen L Storr
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
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Storr HL, Prasad R, Temple IK, Metherell LA, Savage MO, Walker JM. Heterogeneity of the growth phenotype and birth size in acid-labile subunit (ALS) deficiency. J Endocrinol Invest 2015; 38:407-12. [PMID: 25352235 DOI: 10.1007/s40618-014-0195-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 10/10/2014] [Indexed: 10/24/2022]
Abstract
PURPOSE The IGFALS gene encodes the acid-labile subunit (ALS) protein, which regulates circulating IGF-1. Human IGFALS mutations cause growth hormone insensitivity (GHI) associated with ALS, IGF-1 and IGFBP-3 deficiencies and mild to moderate postnatal growth impairment (height SDS -2 to -4). Prenatal growth impairment is not a recognised feature of this disorder, but heterozygous carriers may show an intermediate phenotype. METHODS We report a family of five subjects, including three children born small for gestational age, who were investigated for IGFALS gene mutations. RESULTS The proband, an 8.7 years female with pre- and postnatal growth failure (BW SDS -3.04, Ht SDS -3.86) and biochemical features of GHI, had a homozygous mutation of IGFALS, c.401T>A; p.L134Q. Her 6.1 years brother (BW SDS -2.11, Ht SDS -2.0) had the same homozygous IGFALS mutation. Both parents [adult height SDS -1.76 (father) and -1.82 (mother)] and her 2.7 years sister (BW SDS -2.60, Ht SDS -2.04) were heterozygous for the IGFALS mutation. CONCLUSION Significant phenotypic heterogeneity was observed between family members, in particular varying degrees of prenatal growth retardation were present in the three siblings, which may have contributed to the variation in the postnatal growth phenotype.
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Affiliation(s)
- H L Storr
- Centre for Endocrinology, John Vane Science Centre, William Harvey Research Institute (WHRI), Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK.
| | - R Prasad
- Centre for Endocrinology, John Vane Science Centre, William Harvey Research Institute (WHRI), Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - I K Temple
- Faculty of Medicine, University of Southampton, Southampton, UK
| | - L A Metherell
- Centre for Endocrinology, John Vane Science Centre, William Harvey Research Institute (WHRI), Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - M O Savage
- Centre for Endocrinology, John Vane Science Centre, William Harvey Research Institute (WHRI), Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, UK
| | - J M Walker
- Department of Paediatric Endocrinology, Portsmouth Hospitals National Health Service Trust, Portsmouth, UK
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Poukoulidou T, Kowalczyk J, Metherell L, De Schepper J, Maes M. A novel homozygous mutation of the IGFALS gene in a female adolescent: indirect evidence for a contributing role of the circulating IGF-I pool in the pubertal growth spurt. Horm Res Paediatr 2015; 81:422-7. [PMID: 24819402 DOI: 10.1159/000358329] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 12/31/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Mutations of the IGFALS gene have been reported since 2004 in 24 patients, but only 5 of these are females. CASE REPORT We describe a 14.7-year-old female of a consanguineous Moroccan family with growth retardation and normal-onset but slow progression of puberty without manifest pubertal height gain. RESULTS At age 3.2 years, the patient's height was 85.5 cm (-2.9 SDS) and her weight 9.9 kg (-2.9 SDS) with a head circumference of 44.5 cm (-3.3 SDS). Serum IGF-I and IGFBP-3 concentrations were low with normal basal and stimulated growth hormone (GH) levels. An IGF-I generation test confirmed a lack of response to GH administration. While onset of puberty occurred at a normal age, no significant pubertal growth acceleration was observed despite progression of breast development. Sequencing of the IGFALS gene revealed a novel homozygous frameshift mutation (c.1291delT) with a stop codon (p.W431GfsX10) leading to undetectable serum levels of acid-labile subunit. CONCLUSION We report the phenotype of an adolescent girl with primary IGF-I deficiency due to a novel homozygous mutation of the IGFALS gene, who presented with growth delay, normal pubertal onset with slow progression and no pubertal growth acceleration indirectly suggesting a contributing role of the circulating IGF-I pool in the pubertal growth spurt.
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Affiliation(s)
- Thekla Poukoulidou
- Division of Pediatric Endocrinology, Department of Pediatrics, Cliniques Universitaires Saint-Luc, Catholic University of Louvain, Brussels, Belgium
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Storr HL, Dunkel L, Kowalczyk J, Savage MO, Metherell LA. Genetic characterisation of a cohort of children clinically labelled as GH or IGF1 insensitive: diagnostic value of serum IGF1 and height at presentation. Eur J Endocrinol 2015; 172:151-61. [PMID: 25411237 DOI: 10.1530/eje-14-0541] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE AND DESIGN GH insensitivity (GHI) encompasses growth failure, low serum IGF1 and normal/elevated serum GH. By contrast, IGF1 insensitivity results in pre- and postnatal growth failure associated with relatively high IGF1 levels. From 2008 to 2013, 72 patients from 68 families (45M), mean age 7.1 years (0.4-17.0) with short stature (mean height SDS -3.9; range -9.4 to -1.5), were referred for sequencing. METHODS As a genetics referral centre, we have sequenced appropriate candidate genes (GHR, including its pseudoexon (6Ψ), STAT5B, IGFALS, IGF1, IGF1R, OBSL1, CUL7 and CCDC8) in subjects referred with suspected GHI (n=69) or IGF1 insensitivity (n=3). RESULTS Mean serum IGF1 SDS was -2.7 (range -0.9 to -8.2) in GHI patients and 2.0, 3.7 and 4.4 in patients with suspected IGF1 insensitivity. Out of 69 GHI patients, 16 (23%) (19% families) had mutations in GH-IGF1 axis genes: homozygous GHR (n=13; 6 6Ψ, two novel IVS5ds+1 G to A) and homozygous IGFALS (n=3; one novel c.1291delT). In the GHI groups, two homozygous OBSL1 mutations were also identified (height SDS -4.9 and -5.7) and two patients had hypomethylation in imprinting control region 1 in 11p15 or mUPD7 consistent with Silver-Russell syndrome (SRS) (height SDS -3.7 and -4.3). A novel heterozygous IGF1R (c.112G>A) mutation was identified in one out of three (33%) IGF1-insensitive subjects. CONCLUSION Genotyping contributed to the diagnosis of children with suspected GHI and IGF1 insensitivity, particularly in the GHI subjects with low serum IGF1 SDS (<-2.0) and height SDS (<-2.5). Diagnoses with similar phenotypes included SRS and 3-M syndrome. In 71% patients, no diagnosis was defined justifying further genetic investigation.
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Affiliation(s)
- Helen L Storr
- Barts and the London School of Medicine and DentistryWilliam Harvey Research Institute, Centre for Endocrinology, Queen Mary University of London, London, UK
| | - Leo Dunkel
- Barts and the London School of Medicine and DentistryWilliam Harvey Research Institute, Centre for Endocrinology, Queen Mary University of London, London, UK
| | - Julia Kowalczyk
- Barts and the London School of Medicine and DentistryWilliam Harvey Research Institute, Centre for Endocrinology, Queen Mary University of London, London, UK
| | - Martin O Savage
- Barts and the London School of Medicine and DentistryWilliam Harvey Research Institute, Centre for Endocrinology, Queen Mary University of London, London, UK
| | - Louise A Metherell
- Barts and the London School of Medicine and DentistryWilliam Harvey Research Institute, Centre for Endocrinology, Queen Mary University of London, London, UK
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Domené HM, Scaglia PA, Martínez AS, Keselman AC, Karabatas LM, Pipman VR, Bengolea SV, Guida MC, Ropelato MG, Ballerini MG, Lescano EM, Blanco MA, Heinrich JJ, Rey RA, Jasper HG. Heterozygous IGFALS gene variants in idiopathic short stature and normal children: impact on height and the IGF system. Horm Res Paediatr 2014; 80:413-23. [PMID: 24335034 DOI: 10.1159/000355412] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 08/16/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND In acid-labile subunit (ALS)-deficient families, heterozygous carriers of IGFALS gene mutations are frequently shorter than their wild-type relatives, suggesting that IGFALS haploinsufficiency could result in short stature. We have characterized IGFALS gene variants in idiopathic short stature (ISS) and in normal children, determining their impact on height and the IGF system. PATIENTS AND METHODS In 188 normal and 79 ISS children levels of IGF-1, IGFBP-3, ALS, ternary complex formation (TCF) and IGFALS gene sequence were determined. RESULTS In sum, 9 nonsynonymous or frameshift IGFALS variants (E35Gfs*17, G83S, L97F, R277H, P287L, A330D, R493H, A546V and R548W) were found in 10 ISS children and 6 variants (G170S, V239M, N276S, R277H, G506R and R548W) were found in 7 normal children. If ISS children were classified according to the ability for TCF enhanced by the addition of rhIGFBP-3 (TCF+), carriers of pathogenic IGFALS gene variants were shorter and presented lower levels of IGF-1, IGFBP-3 and ALS in comparison to carriers of benign variants. In ISS families, subjects carrying pathogenic variants were shorter and presented lower IGF-1, IGFBP-3 and ALS levels than noncarriers. CONCLUSIONS These findings suggest that heterozygous IGFALS gene variants could be responsible for short stature in a subset of ISS children with diminished levels of IGF-1, IGFBP-3 and ALS.
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Affiliation(s)
- Horacio M Domené
- Centro de Investigaciones Endocrinológicas 'Dr. César Bergadá' (CEDIE), CONICET - FEI - División de Endocrinología, Hospital de Niños 'Ricardo Gutiérrez', Buenos Aires, Argentina
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12
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Tseng YM, Hwang YS, Lu CL, Lin SJ, Tsai WH. Association of umbilical cord plasma acid-labile subunit of the insulin-like growth factor ternary complex with anthropometry in term newborns. Pediatr Neonatol 2014; 55:139-44. [PMID: 24211220 DOI: 10.1016/j.pedneo.2013.09.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 08/22/2013] [Accepted: 09/03/2013] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Birth size can affect neonatal morbidity and mortality. The insulin-like growth factor (IGF) system is the most important endocrine factor influencing fetal growth. In the circulation, IGFs (mostly IGF-I) are bound to IGF-binding protein 3 (IGFBP-3) and an acid-labile subunit (ALS) to form a ternary complex. The ALS protects IGFs from decay and facilitates their endocrine activity. However, the function of ALS in fetal growth has not yet been fully determined. METHODS Venous umbilical plasma samples were obtained from 98 term neonates and analyzed using enzyme-linked immunosorbent assays. The ALS, IGF-I, and IGFBP-3 umbilical cord plasma levels were analyzed for their association with anthropometric measurements of the neonates. RESULTS The ALS, IGF-I, and IGFBP-3 cord plasma levels were positively correlated with birth weight (r = 0.42, p < 0.001; r = 0.43, p < 0.001; and r = 0.27, p < 0.01, respectively) and placental weight (r = 0.37, p < 0.001; r = 0.31, p < 0.01; and r = 0.30, p < 0.01, respectively). In addition, the ALS cord plasma levels were also positively correlated with head circumference (r = 0.29, p < 0.01). Multiple linear regression analyses showed that both ALS and IGF-I cord plasma levels were independent predictive variables for birth weight (p < 0.01 and p < 0.005, respectively). The ALS cord plasma levels were the only independent predictive variables, however, for head circumference and placental weight (p < 0.01 and p < 0.05, respectively). CONCLUSION The ALS umbilical cord plasma levels are one important factor, in addition to IGF-I, in the IGF system for predicting birth anthropometry, at least for near-term gestation. Our results suggest that the influence of ALS on the IGF system may develop prior to birth and affect fetal growth.
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Affiliation(s)
- Yen-Ming Tseng
- Division of Neonatology, Department of Pediatrics, Chi Mei Medical Center, Tainan, Taiwan
| | - Yea-Shwu Hwang
- Department of Occupational Therapy, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chin-Li Lu
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
| | - Shio-Jean Lin
- Department of Pediatrics, Chi Mei Medical Center, Tainan, Taiwan
| | - Wen-Hui Tsai
- Division of Neonatology, Department of Pediatrics, Chi Mei Medical Center, Tainan, Taiwan.
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13
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Högler W, Martin DD, Crabtree N, Nightingale P, Tomlinson J, Metherell L, Rosenfeld R, Hwa V, Rose S, Walker J, Shaw N, Barrett T, Frystyk J. IGFALS gene dosage effects on serum IGF-I and glucose metabolism, body composition, bone growth in length and width, and the pharmacokinetics of recombinant human IGF-I administration. J Clin Endocrinol Metab 2014; 99:E703-12. [PMID: 24423360 DOI: 10.1210/jc.2013-3718] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
CONTEXT Acid labile subunit (ALS) deficiency, caused by IGFALS mutations, is a subtype of primary IGF-I deficiency (PIGFD) and has been associated with insulin resistance (IR) and osteopenia. Whether patients respond to recombinant human IGF-I (rhIGF-I) is unknown. OBJECTIVE AND DESIGN This study determined the 14-hour pharmacokinetic response of free and total IGF-I and IGF binding protein 3 (IGFBP-3) to a single sc dose of rhIGF-I (120 μg/kg) in four ALS-deficient patients, compared with severe PIGFD, moderate PIGFD, and controls. Intravenous glucose tolerance tests, fasting blood levels, dual-energy X-ray absorptiometry, peripheral quantitative computed tomography, and metacarpal radiogrammetry were performed in the four patients and 12 heterozygous family members. RESULTS IGF-I and IGFBP-3 increased above baseline (P < .05) for 2.5 hours, returning to baseline 7 hours after rhIGF-I injection. Mean (SD) IGF-I Z-score increased by 2.49 (0.90), whereas IGFBP-3 Z-score increased by 0.57 (0.10) only. IGF-I elimination rates in ALS deficiency were similar, but the IGF-I increment was lower than those for severe PIGFD. Significant gene dosage effects were found for all IGF-I peptides, height, forearm muscle size, and metacarpal width. Bone analysis showed that ALS deficiency creates a phenotype of slender bones with normal size-corrected density. Abnormal glucose handling and IR was found in three of four patients and 6 of 12 carriers. CONCLUSIONS These gene dosage effects demonstrate that one functional IGFALS allele is insufficient to maintain normal ALS levels, endocrine IGF-I action, full growth potential, muscle size, and periosteal expansion. Similar gene dosage effects may exist for parameters of IR. Despite similar IGF-I elimination compared with severe PIGFD, ALS-deficient patients cannot mount a similar response. Alternative ways of rhIGF-I administration should be sought.
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Affiliation(s)
- Wolfgang Högler
- Departments of Endocrinology and Diabetes (W.H., N.S., T.B.) and Nuclear Medicine (N.C.), Birmingham Children's Hospital, B4 6NH Birmingham, United Kingdom; Department of Paediatric Endocrinology and Diabetes (D.D.M.), University Children's Hospital, D-72074 Tübingen, Germany; Wellcome Trust Clinical Research Facility (P.N.), Queen Elizabeth Hospital, Birmingham B15 2TH, United Kingdom; School of Clinical and Experimental Medicine (J.T., T.B.), University of Birmingham, Birmingham B15 2TT, United Kingdom; William Harvey Research Institute (L.M.), Barts and the London School of Medicine, Queen Mary University of London, London E1 1BB, United Kingdom; Department of Paediatrics (R.R.), Oregon Health Sciences University, Portland, Oregon 97239; Department of Paediatrics (S.R.), Heartlands Hospital, B9 5SS Birmingham, United Kingdom; Department of Paediatrics (J.W.), Portsmouth Hospital, Portsmouth PO6 3LY, United Kingdom; and Medical Research Laboratory (J.F.), Department of Clinical Medicine, Faculty of Health, Aarhus University, and Department of Endocrinology and Internal Medicine, Aarhus University Hospital, DK-8000 C Aarhus, Denmark
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14
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Hess O, Khayat M, Hwa V, Heath KE, Teitler A, Hritan Y, Allon-Shalev S, Tenenbaum-Rakover Y. A novel mutation in IGFALS, c.380T>C (p.L127P), associated with short stature, delayed puberty, osteopenia and hyperinsulinaemia in two siblings: insights into the roles of insulin growth factor-1 (IGF1). Clin Endocrinol (Oxf) 2013; 79:838-44. [PMID: 23488611 DOI: 10.1111/cen.12200] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 02/17/2013] [Accepted: 03/08/2013] [Indexed: 12/31/2022]
Abstract
BACKGROUND The acid-labile subunit (ALS) protein is crucial for maintaining the circulating IGF/IGFBP system. Inactivating mutations of IGFALS result in IGF1 deficiency associated with growth retardation. Although the first IGFALS mutation in humans was described in 2004, only 16 mutations have been reported since. Moreover, the phenotype of affected patients as a consequence of ALS deficiency is still highly variable. We assessed whether children with idiopathic short stature (ISS) harbour mutations in IGFALS and characterized affected patients' phenotype. DESIGN Sixty-five children with ISS were enrolled in the study. Serum ALS levels were measured by ELISA, and IGFALS was sequenced. RESULTS A novel homozygous mutation in IGFALS, c.380T>C (p.L127P), was identified in two siblings of a consanguineous family. The proband, a 17·75-year-old male, was -1·9 SDS in height and -4·5 SDS in weight. Exaggerated stimulated GH (38 ng/ml) and extremely low IGF1 and IGFBP3 (<25 and <500 ng/ml, respectively) indicated GH insensitivity. Both affected siblings had low or no ALS (43 and 0 mU/ml, respectively). They were also mildly small for gestational age, severely underweight and showed osteopenia, insulin insensitivity and delayed and slow puberty progression. CONCLUSIONS Acid-labile subunit deficiency due to IGFALS mutations is a rare cause of growth retardation in children. The unique combination of features presented by the two affected siblings emphasizes the important role of IGF1 in bone formation, insulin regulation and the pubertal process, in addition to its crucial effect on growth. Long-term follow-up is indicated since the clinical outcome with respect to osteoporosis, diabetes mellitus and fertility has not been recognized.
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Affiliation(s)
- Ora Hess
- Pediatric Endocrine Institute, Ha'Emek Medical Center, Afula, Israel
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15
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David A, Kelley LA, Sternberg MJE. A new structural model of the acid-labile subunit: pathogenetic mechanisms of short stature-causing mutations. J Mol Endocrinol 2012; 49:213-20. [PMID: 22991227 DOI: 10.1530/jme-12-0086] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The acid-labile subunit (ALS) is the main regulator of IGF1 and IGF2 bioavailability. ALS deficiency caused by mutations in the ALS (IGFALS) gene often results in mild short stature in adulthood. Little is known about the ALS structure-function relationship. A structural model built in 1999 suggested a doughnut shape, which has never been observed in the leucine-rich repeat (LRR) superfamily, to which ALS belongs. In this study, we built a new ALS structural model, analysed its glycosylation and charge distribution and studied mechanisms by which missense mutations affect protein structure. We used three structure prediction servers and integrated their results with information derived from ALS experimental studies. The ALS model was built at high confidence using Toll-like receptor protein templates and resembled a horseshoe with an extensively negatively charged concave surface. Enrichment in prolines and disulphide bonds was found at the ALS N- and C-termini. Moreover, seven N-glycosylation sites were identified and mapped. ALS mutations were predicted to affect protein structure by causing loss of hydrophobic interactions (p.Leu134Gln), alteration of the amino acid backbone (p.Leu241Pro, p.Leu172Phe and p.Leu244Phe), loss of disulphide bridges (p.Cys60Ser and p.Cys540Arg), change in structural constrains (p.Pro73Leu), creation of novel glycosylation sites (p.Asp440Asn) or alteration of LRRs (p.Asn276Ser). In conclusion, our ALS structural model was identified as a highly confident prediction by three independent methods and disagrees with the previously published ALS model. The new model allowed us to analyse the ALS core and its caps and to interpret the potential structural effects of ALS mutations.
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Affiliation(s)
- Alessia David
- Centre for Integrative Systems Biology and Bioinformatics, Division of Molecular Biosciences, Department of Life Sciences, Imperial College London, London SW7 2AZ, UK.
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16
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Guo J, Jorjani H, Carlborg Ö. A genome-wide association study using international breeding-evaluation data identifies major loci affecting production traits and stature in the Brown Swiss cattle breed. BMC Genet 2012; 13:82. [PMID: 23031427 PMCID: PMC3548702 DOI: 10.1186/1471-2156-13-82] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 09/22/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The genome-wide association study (GWAS) is a useful approach to identify genes affecting economically important traits in dairy cattle. Here, we report the results from a GWAS based on high-density SNP genotype data and estimated breeding values for nine production, fertility, body conformation, udder health and workability traits in the Brown Swiss cattle population that is part of the international genomic evaluation program. RESULT GWASs were performed using 50 k SNP chip data and deregressed estimated breeding values (DEBVs) for nine traits from between 2061 and 5043 bulls that were part of the international genomic evaluation program coordinated by Interbull Center. The nine traits were milk yield (MY), fat yield (FY), protein yield (PY), lactating cow's ability to recycle after calving (CRC), angularity (ANG), body depth (BDE), stature (STA), milk somatic cell score (SCS) and milk speed (MSP). Analyses were performed using a linear mixed model correcting for population confounding. A total of 74 SNPs were detected to be genome-wide significantly associated with one or several of the nine analyzed traits. The strongest signal was identified on chromosome 25 for milk production traits, stature and body depth. Other signals were on chromosome 11 for angularity, chromosome 24 for somatic cell score, and chromosome 6 for milking speed. Some signals overlapped with earlier reported QTL for similar traits in other cattle populations and were located close to interesting candidate genes worthy of further investigations. CONCLUSIONS Our study shows that international genetic evaluation data is a useful resource for identifying genetic factors influencing complex traits in livestock. Several genome wide significant association signals could be identified in the Brown Swiss population, including a major signal on BTA25. Our findings report several associations and plausible candidate genes that deserve further exploration in other populations and molecular dissection to explore the potential economic impact and the genetic mechanisms underlying these production traits in cattle.
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Affiliation(s)
- Jiazhong Guo
- College of Animal Science and Technology, Northwest A&F University,Yangling, Shaanxi 712100, People’s Republic of China.
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17
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Backeljauw PF, Chernausek SD. The insulin-like growth factors and growth disorders of childhood. Endocrinol Metab Clin North Am 2012; 41:265-82, v. [PMID: 22682630 DOI: 10.1016/j.ecl.2012.04.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Specific lesions of the growth hormone (GH)/insulin-like growth factor (IGF) axis have been identified in humans, each of which has distinctive auxologic and biochemical features. Measures of circulating IGF-I are useful in diagnosing growth disorders in childhood and in evaluating response to GH therapy. Recombinant human IGF-I is an effective treatment of severe primary IGF deficiency, which is typical of patients with GH receptor defects (Laron syndrome). Such treatment has been limited to a few severely affected patients. Future studies will provide new insight into IGF-I as treatment and into the nature of growth disorders that involve the IGF axis.
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Affiliation(s)
- Philippe F Backeljauw
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, 3333 Burnett Avenue, Cincinnati, OH 45229, USA
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18
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Saenger P, Reiter E. Genetic factors associated with small for gestational age birth and the use of human growth hormone in treating the disorder. INTERNATIONAL JOURNAL OF PEDIATRIC ENDOCRINOLOGY 2012; 2012:12. [PMID: 22587301 PMCID: PMC3511163 DOI: 10.1186/1687-9856-2012-12] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Accepted: 03/19/2012] [Indexed: 12/31/2022]
Abstract
The term small for gestational age (SGA) refers to infants whose birth weights and/or lengths are at least two standard deviation (SD) units less than the mean for gestational age. This condition affects approximately 3%–10% of newborns. Causes for SGA birth include environmental factors, placental factors such as abnormal uteroplacental blood flow, and inherited genetic mutations. In the past two decades, an enhanced understanding of genetics has identified several potential causes for SGA. These include mutations that affect the growth hormone (GH)/insulin-like growth factor (IGF)-1 axis, including mutations in the IGF-1 gene and acid-labile subunit (ALS) deficiency. In addition, select polymorphisms observed in patients with SGA include those involved in genes associated with obesity, type 2 diabetes, hypertension, ischemic heart disease and deletion of exon 3 growth hormone receptor (d3-GHR) polymorphism. Uniparental disomy (UPD) and imprinting effects may also underlie some of the phenotypes observed in SGA individuals. The variety of genetic mutations associated with SGA births helps explain the diversity of phenotype characteristics, such as impaired motor or mental development, present in individuals with this disorder. Predicting the effectiveness of recombinant human GH (hGH) therapy for each type of mutation remains challenging. Factors affecting response to hGH therapy include the dose and method of hGH administration as well as the age of initiation of hGH therapy. This article reviews the results of these studies and summarizes the success of hGH therapy in treating this difficult and genetically heterogenous disorder.
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Affiliation(s)
- Paul Saenger
- Albert Einstein College of Medicine, Winthrop University Hospital, 120 Mineola Boulevard, Mineola, NY, 13501, USA.
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19
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Savage MO, Hwa V, David A, Rosenfeld RG, Metherell LA. Genetic Defects in the Growth Hormone-IGF-I Axis Causing Growth Hormone Insensitivity and Impaired Linear Growth. Front Endocrinol (Lausanne) 2011; 2:95. [PMID: 22654835 PMCID: PMC3356141 DOI: 10.3389/fendo.2011.00095] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Accepted: 11/21/2011] [Indexed: 11/13/2022] Open
Abstract
Human genetic defects in the growth hormone (GH)-IGF-I axis affecting the IGF system present with growth failure as their principal clinical feature. This is usually associated with GH insensitivity (GHI) presenting in childhood as severe or mild short stature. Dysmorphic features and metabolic abnormalities may also be present. The field of GHI due to mutations affecting GH action has evolved rapidly since the first description of the extreme phenotype related to homozygous GH receptor (GHR) mutations in 1966. A continuum of genetic, phenotypic, and biochemical abnormalities can be defined associated with clinically relevant defects in linear growth. The mechanisms of the GH-IGF-I axis in the regulation of normal human growth is discussed followed by descriptions of mutations in GHR, STAT5B, IGF-I, IGFALS, IGF1R, and GH1 defects causing bio-inactive GH or anti-GH antibodies. These GH-IGF-I axis defects are associated with a range of clinical, and hormonal characteristics. An up-dated approach to the clinical assessment of the patient with GHI focusing on investigation of the GH-IGF-I axis and relevant molecular studies contributing to the identification of causative genetic defects is also discussed.
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Affiliation(s)
- Martin O. Savage
- Department of Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and DentistryLondon, UK
| | - Vivian Hwa
- Department of Pediatrics, Oregon Health and Science UniversityPortland, OR, USA
| | - Alessia David
- Department of Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and DentistryLondon, UK
| | - Ron G. Rosenfeld
- Department of Pediatrics, Oregon Health and Science UniversityPortland, OR, USA
| | - Louise A. Metherell
- Department of Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and DentistryLondon, UK
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David A, Hwa V, Metherell LA, Netchine I, Camacho-Hübner C, Clark AJL, Rosenfeld RG, Savage MO. Evidence for a continuum of genetic, phenotypic, and biochemical abnormalities in children with growth hormone insensitivity. Endocr Rev 2011; 32:472-97. [PMID: 21525302 DOI: 10.1210/er.2010-0023] [Citation(s) in RCA: 132] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
GH insensitivity (GHI) presents in childhood as growth failure and in its severe form is associated with dysmorphic and metabolic abnormalities. GHI may be caused by genetic defects in the GH-IGF-I axis or by acquired states such as chronic illness. This article discusses the former category. The field of GHI due to mutations affecting GH action has evolved considerably since the original description of the extreme phenotype related to homozygous GH receptor (GHR) mutations over 40 yr ago. A continuum of genetic, phenotypic, and biochemical abnormalities can be defined associated with clinically relevant defects in linear growth. The role and mechanisms of the GH-IGF-I axis in normal human growth is discussed, followed by descriptions of mutations in GHR, STAT5B, PTPN11, IGF1, IGFALS, IGF1R, and GH1 defects causing bioinactive GH or anti-GH antibodies. These defects are associated with a range of genetic, clinical, and hormonal characteristics. Genetic abnormalities causing growth failure that is less severe than the extreme phenotype are emphasized, together with an analysis of height and serum IGF-I across the spectrum of different types of GHR defects. An overall view of genotype and phenotype relationships is presented, together with an updated approach to the assessment of the patient with GHI, focusing on investigation of the GH-IGF-I axis and relevant molecular studies contributing to this diagnosis.
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Affiliation(s)
- Alessia David
- Department of Endocrinology, Barts and the London School of Medicine and Dentistry, London, United Kingdom
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21
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Abstract
The acid-labile subunit (ALS) protein is crucial for maintaining the integrity of the circulating IGF/IGFBP system. In humans, complete ALS deficiency is characterized by severely reduced serum IGF-I and IGFBP-3 concentrations that is incongruent with the associated mild growth retardation (height SDS -2 to -3 SDS before and during puberty). Twenty-one patients have been described with ALS deficiency, representing 16 unique homozygous or compound heterozygous inactivating mutations of the IGFALS gene. Pubertal delay in boys and insulin insensitivity are common findings. In the assessment of a child with short stature ALS deficiency should be consider in those patients presenting: 1) a normal response to GH stimulation test, 2) low IGF-I levels associated with more profoundly reduced IGFBP-3 levels, 3) a mild growth retardation, apparently out of proportion to the degree of IGF-I and IGFBP-3 deficits, 4) lack of response to an IGF generation test and 5) insulin insensitivity.
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Affiliation(s)
- Horacio M Domené
- Centro de Investigaciones Endocrinológicas, División de Endocrinología, Hospital de Niños R Gutiérrez, Gallo 1330, Buenos Aires, Argentina
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22
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Firth SM, Yan X, Baxter RC. D440N mutation in the acid-labile subunit of insulin-like growth factor complexes inhibits secretion and complex formation. Mol Endocrinol 2010; 25:307-14. [PMID: 21177759 DOI: 10.1210/me.2010-0295] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The acid-labile subunit (ALS) regulates IGF bioavailability by forming heterotrimeric complexes with IGFs and IGF-binding protein-3 (IGFBP-3). A homozygous missense mutation (D440N) resulting in undetectable circulating levels of ALS with a concomitant reduction in IGF-I and IGFBP-3 has been reported to cause mild growth retardation. To understand how this particular mutation affects ALS circulating levels and IGF-transport function, we expressed recombinant ALS and its variants, D440N-ALS, T442A-ALS, and D440N/T442A-ALS, using adenovirus vectors. Compared with wild-type ALS, the secretion of D440N-ALS was 80% lower. The D440N mutation was proposed to generate an N-glycosylation site additional to the seven existing motifs in ALS. D440N-ALS appeared larger than ALS, attributable to N-linked glycans because deglycosylation with N-glycosidase F reduced both proteins to the same molecular mass. When ALS was incubated with IGF-I and IGFBP-3, 70-80% of IGF-I was detected by gel-filtration chromatography in forms corresponding to the 150-kDa ternary complex. In contrast, when D440N-ALS was tested, less than 30% of IGF-I was found in high molecular mass complexes. Two other ALS variants mutated in the same putative glycosylation site, D440N/T442A-ALS and T442A-ALS, showed similar chromatographic profiles to wild-type ALS. The D440N mutation in ALS generates a hyperglycosylated form with impaired secretion and complex formation, potentially leading to dysregulation of endocrine IGF, thus contributing to the growth retardation observed in the affected patient. This is the first study to explain how a natural mutation, D440N, in ALS impairs its function.
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Affiliation(s)
- Sue M Firth
- Kolling Institute of Medical Research, University of Sydney, Royal North Shore Hospital, St Leonards, New South Wales 2065, Australia.
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