1
|
Sukri A, Noorizhab MNF, Teh LK, Salleh MZ. Insight of the mitochondrial genomes of the Orang Asli and Malays: The heterogeneity and the disease-associated variants. Mitochondrion 2021; 62:74-84. [PMID: 34748985 DOI: 10.1016/j.mito.2021.10.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 10/27/2021] [Accepted: 10/28/2021] [Indexed: 11/27/2022]
Abstract
Orang Asli are the oldest inhabitants in Peninsular Malaysia that forms as a national minority while the Malays are the majority. The study aimed to screen the mitochondrial genomes of the Orang Asli and the Malays to discover the disease-associated variants. A total of 99 Orang Asli from six tribes (Bateq, Cheq Wong, Orang Kanaq, Kensiu, Lanoh, and Semai) were recruited. Mitochondrial genome sequencing was conducted using a next-generation sequencing platform. Furthermore, we retrieved mitochondrial DNA sequences from the Malays for comparison. The clinical significance, pathogenicity prediction and frequency of variants were determined using online tools. Variants associated with mitochondrial diseases were detected in the 2 populations. A high frequency of variants associated with mitochondrial diseases, breast cancer, prostate cancer, and cervical cancer were detected in the Orang Asli and modern Malays. As medicine evolves to adopt prediction and prevention of diseases, this study highlights the need for intervention to adopt genomics medicine to strategise better healthcare management as a way forward for Precision Health.
Collapse
Affiliation(s)
- Asif Sukri
- Integrative Pharmacogenomics Institute, Universiti Teknologi MARA Cawangan Selangor, Puncak Alam Campus, 42300 Puncak Alam, Selangor, Malaysia
| | - Mohd Nur Fakhruzzaman Noorizhab
- Integrative Pharmacogenomics Institute, Universiti Teknologi MARA Cawangan Selangor, Puncak Alam Campus, 42300 Puncak Alam, Selangor, Malaysia; Faculty of Pharmacy, Universiti Teknologi MARA Cawangan Selangor, Puncak Alam Campus, 42300 Puncak Alam, Selangor, Malaysia
| | - Lay Kek Teh
- Integrative Pharmacogenomics Institute, Universiti Teknologi MARA Cawangan Selangor, Puncak Alam Campus, 42300 Puncak Alam, Selangor, Malaysia; Faculty of Pharmacy, Universiti Teknologi MARA Cawangan Selangor, Puncak Alam Campus, 42300 Puncak Alam, Selangor, Malaysia
| | - Mohd Zaki Salleh
- Integrative Pharmacogenomics Institute, Universiti Teknologi MARA Cawangan Selangor, Puncak Alam Campus, 42300 Puncak Alam, Selangor, Malaysia.
| |
Collapse
|
2
|
Tabebi M, Safi W, Felhi R, Alila Fersi O, Keskes L, Abid M, Mnif M, Fakhfakh F. The first concurrent detection of mitochondrial DNA m.3243A>G mutation, deletion, and depletion in a family with mitochondrial diabetes. Mol Genet Genomic Med 2020; 8:e1292. [PMID: 32394641 PMCID: PMC7336730 DOI: 10.1002/mgg3.1292] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 04/09/2020] [Accepted: 04/13/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Mitochondrial diabetes (MD) is a rare monogenic form of diabetes and divided into type l and type 2. It is characterized by a strong familial clustering of diabetes with the presence of maternal transmission in conjunction with bilateral hearing impairment in most of the carriers. The most common form of MD is associated with the m.3243A>G mutation in the mitochondrial MT-TL1, but there are also association with a range of other point mutations, deletion, and depletion in mtDNA. METHODS The mitochondrial genome anomalies were investigated in a family with clinical features of MD, which includes a proband presenting severe MD conditions including cardiomyopathy, retinopathy, and psychomotor retardation. RESULTS By investigating the patient's blood leukocytes and skeletal muscle, we identified the m.3243A>G mutation in heteroplasmic state. This mutation was absent in the rest of the family members. In addition, our analysis revealed in the proband a large mtDNA heteroplasmic deletion (~1 kb) and a reduction in mtDNA copy number. CONCLUSION Our study points out, for the first time, a severe phenotypic expression of the m.3243A>G point mutation in association with mtDNA deletion and depletion in MD.
Collapse
Affiliation(s)
- Mouna Tabebi
- Molecular and Functional Genetics Laboratory, Faculty of Science of Sfax, University of Sfax, Sfax, Tunisia.,Human Molecular Genetics Laboratory, Faculty of Medicine of Sfax, University of Sfax, Sfax, Tunisia
| | - Wajdi Safi
- Department of Endocrinology Diabetology, CHU Hedi Chaker, Sfax, Tunisia
| | - Rahma Felhi
- Molecular and Functional Genetics Laboratory, Faculty of Science of Sfax, University of Sfax, Sfax, Tunisia
| | - Olfa Alila Fersi
- Molecular and Functional Genetics Laboratory, Faculty of Science of Sfax, University of Sfax, Sfax, Tunisia
| | - Leila Keskes
- Human Molecular Genetics Laboratory, Faculty of Medicine of Sfax, University of Sfax, Sfax, Tunisia
| | - Mohamed Abid
- Department of Endocrinology Diabetology, CHU Hedi Chaker, Sfax, Tunisia
| | - Mouna Mnif
- Department of Endocrinology Diabetology, CHU Hedi Chaker, Sfax, Tunisia
| | - Faiza Fakhfakh
- Molecular and Functional Genetics Laboratory, Faculty of Science of Sfax, University of Sfax, Sfax, Tunisia
| |
Collapse
|
3
|
Alexandar SP, Dhinakaran I, Ravi V, Parthasarathy N, Ganesan S, Bhaskaran M, Arun Kumar GP. Meta-Analysis of Association of Mitochondrial DNA Mutations with Type 2 Diabetes and Gestational Diabetes Mellitus. INT J HUM GENET 2018. [DOI: 10.1080/09723757.2018.1430110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Soundarya Priya Alexandar
- Human Genomics Laboratory, School of Chemical & Biotechnology, SASTRA University Thanjavur, Thanjavur 613 401, Tamil Nadu, India
| | - Indhumathi Dhinakaran
- Human Genomics Laboratory, School of Chemical & Biotechnology, SASTRA University Thanjavur, Thanjavur 613 401, Tamil Nadu, India
| | - Vidhya Ravi
- K.A.P. Viswanatham Govt. Medical College, Trichy, 620 001, Tamil Nadu, India
| | - Nandhini Parthasarathy
- Human Genomics Laboratory, School of Chemical & Biotechnology, SASTRA University Thanjavur, Thanjavur 613 401, Tamil Nadu, India
| | - Somasundari Ganesan
- Human Genomics Laboratory, School of Chemical & Biotechnology, SASTRA University Thanjavur, Thanjavur 613 401, Tamil Nadu, India
| | - Muthumeenakshi Bhaskaran
- Human Genomics Laboratory, School of Chemical & Biotechnology, SASTRA University Thanjavur, Thanjavur 613 401, Tamil Nadu, India
| | - Ganesh Prasad Arun Kumar
- Human Genomics Laboratory, School of Chemical & Biotechnology, SASTRA University Thanjavur, Thanjavur 613 401, Tamil Nadu, India
| |
Collapse
|
4
|
Alila OF, Rebai EM, Tabebi M, Tej A, Chamkha I, Tlili A, Bouguila J, Tilouche S, Soyah N, Boughamoura L, Fakhfakh F. Whole mitochondrial genome analysis in two families with dilated mitochondrial cardiomyopathy: detection of mutations in MT-ND2 and MT-TL1 genes. Mitochondrial DNA A DNA Mapp Seq Anal 2015; 27:2873-80. [PMID: 26258512 DOI: 10.3109/19401736.2015.1060417] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Pathogenic mitochondrial DNA (mtDNA) mutations leading to mitochondrial dysfunction can cause cardiomyopathy and heart failure. These mutations were described in the mt-tRNA genes and in the mitochondrial protein-coding genes. The aim of this study was to identify the genetic defect in two patients belonging to two families with cardiac dysfunction associated to a wide spectrum of clinical phenotypes. The sequencing analysis of the whole mitochondrial DNA in the two patients and their parents revealed the presence of known polymorphisms associated to cardiomyopathy and two pathogenic mutations in DNA extracted from blood leucocytes: the heteroplasmic m.3243A > G mutation in the MT-TL1 gene in patient A; and the homoplasmic m.5182C > T mutation in the ND2 gene in patient B. Secondary structure analysis of the ND2 protein further supported the deleterious role of the m.5182C > T mutation, as it was found to be involved an extended imbalance in its hydrophobicity and affect its function. In addition, the mitochondrial variants identified in patients A and B classify both of them in the same haplogroup H2a2a1.
Collapse
Affiliation(s)
- Olfa Fersi Alila
- a Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax , Sfax , Tunisia
| | - Emna Mkaouar Rebai
- a Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax , Sfax , Tunisia
| | - Mouna Tabebi
- a Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax , Sfax , Tunisia
| | - Amel Tej
- b Service de Pédiatrie, C.H.U. Farhat Hached de Sousse , Sousse , Tunisia , and
| | - Imen Chamkha
- a Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax , Sfax , Tunisia
| | - Abdelaziz Tlili
- c Department of Applied Biology , College of Sciences, University of Sharjah , Sharjah , UAE
| | - Jihene Bouguila
- b Service de Pédiatrie, C.H.U. Farhat Hached de Sousse , Sousse , Tunisia , and
| | - Samia Tilouche
- b Service de Pédiatrie, C.H.U. Farhat Hached de Sousse , Sousse , Tunisia , and
| | - Nejla Soyah
- b Service de Pédiatrie, C.H.U. Farhat Hached de Sousse , Sousse , Tunisia , and
| | - Lamia Boughamoura
- b Service de Pédiatrie, C.H.U. Farhat Hached de Sousse , Sousse , Tunisia , and
| | - Faiza Fakhfakh
- a Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax , Sfax , Tunisia
| |
Collapse
|
5
|
Khan IA, Shaik NA, Pasupuleti N, Chava S, Jahan P, Hasan Q, Rao P. Screening of mitochondrial mutations and insertion-deletion polymorphism in gestational diabetes mellitus in the Asian Indian population. Saudi J Biol Sci 2015; 22:243-8. [PMID: 25972744 PMCID: PMC4423658 DOI: 10.1016/j.sjbs.2014.11.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Revised: 10/29/2014] [Accepted: 11/02/2014] [Indexed: 11/23/2022] Open
Abstract
In this study we scrutinized the association between the A8344G/A3243G mutations and a 9-bp deletion polymorphism with gestational diabetes mellitus (GDM) in an Asian Indian population. The A3243G mutation in the mitochondrial tRNA(Leu(UUR)) causes mitochondrial encephalopathy myopathy, lactic acidosis, and stroke-like episodes (MELAS), while the A8344G mutation in tRNA(Lys) causes myoclonus epilepsy with ragged red fibers (MERRF). We screened 140 pregnant women diagnosed with GDM and 140 non-GDM participants for these mutations by PCR-RFLP analysis. Both A3243G and A8344G were associated with GDM (A3243: OR-3.667, 95% CI = 1.001-13.43, p = 0.03; A8344G: OR-11.00, 95% CI = 0.6026-200.8, p = 0.04). Mitochondrial DNA mutations contribute to the development of GDM. Our results conclude that mitochondrial mutations are associated with the GDM women in our population. Thus it is important to screen other mitochondrial mutations in the GDM women.
Collapse
Affiliation(s)
- Imran Ali Khan
- Department of Genetics and Molecular Medicine, Kamineni Hospitals, LB Nagar, Hyderabad 500068, India
- Department of Genetics, Vasavi Medical and Research Centre, Lakdikapool, Hyderabad 500004, India
- Department of Genetics and Biotechnology, Osmania University, Tarnaka, Hyderabad 500007, India
| | - Noor Ahmad Shaik
- Department of Genetic Medicine, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Nagarjuna Pasupuleti
- Department of Genetics and Molecular Medicine, Kamineni Hospitals, LB Nagar, Hyderabad 500068, India
| | - Srinivas Chava
- Department of Genetics, Vasavi Medical and Research Centre, Lakdikapool, Hyderabad 500004, India
| | - Parveen Jahan
- Department of Genetics and Biotechnology, Osmania University, Tarnaka, Hyderabad 500007, India
| | - Qurratulain Hasan
- Department of Genetics and Molecular Medicine, Kamineni Hospitals, LB Nagar, Hyderabad 500068, India
- Department of Genetics, Vasavi Medical and Research Centre, Lakdikapool, Hyderabad 500004, India
| | - Pragna Rao
- Department of Biochemistry, Kasturba Medical College, Manipal University, Manipal 576104, Karnataka, India
| |
Collapse
|
6
|
Yano T, Nishio SY, Usami SI. Frequency of mitochondrial mutations in non-syndromic hearing loss as well as possibly responsible variants found by whole mitochondrial genome screening. J Hum Genet 2014; 59:100-6. [PMID: 24401907 PMCID: PMC3970901 DOI: 10.1038/jhg.2013.128] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 10/19/2013] [Accepted: 11/08/2013] [Indexed: 11/09/2022]
Abstract
Mutations in mitochondrial DNA (mtDNA) are reported to be responsible for the pathogenesis of maternally inherited hearing loss. Complete mtDNA sequencing may detect pathogenic mutations, but whether they are indeed pathogenic can be difficult to interpret because of normal ethnic-associated haplogroup variation and other rare variations existing among control populations. In this study, we performed systemic mutational analysis of mtDNA in 394 Japanese patients with hearing loss. Two different cohorts were analyzed in this study: Cohort 1, 254 maternally inherited patients; and Cohort 2, 140 patients with various inheritance modes. After screening of the entire mtDNA genome with direct sequencing, we evaluated the frequency of previously reported mutations and the frequency and pathogenicity of the novel variants. As a result, the 'Confirmed' mitochondrial mutations were found predominantly in Cohort 1 rather than in Cohort 2 (14.6 vs 0.7%). 1555A>G (n=23) is the most common mutation, followed by the 3243A>G (n=11) mutations. On the basis of prediction analysis, we detected 10 novel homoplasmic mitochondrial variants. After further classification, the 3595A>G and 6204A>G variants were found to be new candidate mutations possibly associated with hearing loss.
Collapse
|
7
|
Hsouna S, Ben Halim N, Lasram K, Arfa I, Jamoussi H, Bahri S, Ammar SB, Miladi N, Abid A, Abdelhak S, Kefi R. Association study of mitochondrial DNA polymorphisms with type 2 diabetes in Tunisian population. ACTA ACUST UNITED AC 2013; 26:367-72. [PMID: 24102601 DOI: 10.3109/19401736.2013.836508] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Mitochondrial DNA (mtDNA) variation may play an important role in the pathogenesis of type 2 diabetes (T2Ds). In this study, we aimed to explore whether mtDNA variants contribute to the susceptibility to T2Ds in a Tunisian population. The hypervariable region 1 (HVS1) of the mtDNA of 64 T2Ds patients and 77 healthy controls was amplified and sequenced. Statistical analysis was performed using the STATA program. Analysis of the total screened variants (N = 88) from the HVS1 region showed no significant difference in the distribution of all polymorphisms between T2Ds and controls, except for the variant G16390A which was more frequent in T2Ds (15.9%) than in controls (5.4%) (p = 0.04). The association of G16390A was not detected after multivariate regression analysis. Similarly, analysis of the distribution of mitochondrial haplogroups within our dataset showed 18 distinct major haplogroups with no significant difference between T2Ds and controls. Except, the weakly association found for the G16390A variant, our results showed that none of the tested polymorphisms from the HVS1 region have a major role in T2Ds pathogenesis in the studied Tunisian population even when taking into account the population stratification.
Collapse
Affiliation(s)
- Sana Hsouna
- Biomedical Genomics and Oncogenetics Laboratory (LR 11 IPT 05), Institut Pasteur de Tunis, Université El Manar de Tunis , Tunis , Tunisia
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Mezghani N, Mnif M, Mkaouar-Rebai E, Kallel N, Charfi N, Abid M, Fakhfakh F. A maternally inherited diabetes and deafness patient with the 12S rRNA m.1555A>G and the ND1 m.3308T>C mutations associated with multiple mitochondrial deletions. Biochem Biophys Res Commun 2013; 431:670-4. [DOI: 10.1016/j.bbrc.2013.01.063] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Accepted: 01/16/2013] [Indexed: 11/29/2022]
|
9
|
A novel MT-CO1 m.6498C>A variation associated with the m.7444G>A mutation in the mitochondrial COI/tRNASer(UCN) genes in a patient with hearing impairment, diabetes and congenital visual loss. Biochem Biophys Res Commun 2013; 430:585-91. [DOI: 10.1016/j.bbrc.2012.11.109] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2012] [Accepted: 11/19/2012] [Indexed: 11/18/2022]
|
10
|
A Tunisian patient with Pearson syndrome harboring the 4.977 kb common deletion associated to two novel large-scale mitochondrial deletions. Biochem Biophys Res Commun 2011; 411:381-6. [DOI: 10.1016/j.bbrc.2011.06.154] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Accepted: 06/24/2011] [Indexed: 11/23/2022]
|
11
|
The mitochondrial ND1 m.3337G>A mutation associated to multiple mitochondrial DNA deletions in a patient with Wolfram syndrome and cardiomyopathy. Biochem Biophys Res Commun 2011; 411:247-52. [DOI: 10.1016/j.bbrc.2011.06.106] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Accepted: 06/16/2011] [Indexed: 11/24/2022]
|
12
|
Mezghani N, Mnif M, Kacem M, Mkaouar-Rebai E, Hadj Salem I, Kallel N, charfi N, Abid M, fakhfakh F. A whole mitochondrial genome screening in a MELAS patient: A novel mitochondrial tRNAVal mutation. Biochem Biophys Res Commun 2011; 407:747-52. [DOI: 10.1016/j.bbrc.2011.03.094] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 03/18/2011] [Indexed: 10/18/2022]
|
13
|
Mezghani N, Mkaouar-Rebai E, Mnif M, Charfi N, Rekik N, Youssef S, Abid M, Fakhfakh F. The heteroplasmic m.14709T>C mutation in the tRNA(Glu) gene in two Tunisian families with mitochondrial diabetes. J Diabetes Complications 2010; 24:270-7. [PMID: 20045353 DOI: 10.1016/j.jdiacomp.2009.11.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2009] [Revised: 10/26/2009] [Accepted: 11/18/2009] [Indexed: 11/26/2022]
Abstract
UNLABELLED Diabetes mellitus (DM) is a heterogeneous disorder characterized by the presence of chronic hyperglycemia. Genetic factors play an important role in the development of this disorder, and several studies reported mutations in nuclear genes implicated in the insulin function. Besides, DM can be maternally transmitted in some families, possibly due to the maternal mitochondrial inheritance. In fact, mitochondrial genes may be plausible causative agents for diabetes, since mitochondrial oxidative phosphorylation plays an important role in glucose-stimulated insulin secretion from beta cells. MATERIALS AND METHODS In this report, we screened two Tunisian families with mitochondrial diabetes for the m.3243A>G and the m.14709T>C mutations, respectively, in the tRNA(Leu(UUR)) and the tRNA(Glu) genes. RESULTS The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and the sequence-specific primers by polymerase chain reaction (SSP-PCR) analysis in the leucocytes and the buccal mucosa in the members of the two families showed the absence of the m.3243A>G mutation and the presence of the heteroplasmic m.14709T>C mutation in the tRNA(Glu) gene in the two tested tissues. CONCLUSIONS We conclude that the m.14709T>C mutation in the tRNA(Glu) gene could be a cause of mitochondrial diabetes in Tunisian affected families. In addition, the heteroplasmic loads correlated with the severity and the onset of mitochondrial diabetes in one family but not in the other, suggesting the presence of environmental factors or nuclear modifier genes.
Collapse
Affiliation(s)
- Najla Mezghani
- Faculty of Medicine of Sfax, Human Molecular Genetic Laboratory, Sfax, Tunisia
| | | | | | | | | | | | | | | |
Collapse
|
14
|
Abstract
AbstractThe A3243G mutation in the mitochondrial tRNALeu (UUR) gene is one of the most common causes of mitochondrial DNA related disorders. Originally it was described in MELAS syndrome (Mitochondrial Encephalomyopathy, Lactic acidosis, Stroke-like episodes), later it had been found to be associated with various phenotypes. In our study the mutation frequency of the A3243G mtDNA mutation was investigated in patients with maternal sensoneural hearing loss, stroke-like episodes, ataxia and myopathy with undetermined etiology. We screened 631 Hungarian patients in North-East, South-West and Central Hungary between 1999 and 2008 for this mutation. The mtDNA analysis was performed from blood and/or muscle tissue. The A3243G substitution was present in 6 patients in heteroplasmic form. The segregation analysis detected 8 further cases. The frequency of the A3243G mutation was 2.22% in the investigated patients. The A3243G mutation frequency in Hungary does not differ significantly from other countries using similar patient selection criteria, however in Finland a higher mutation rate was found. In studies investigated the mutation frequency of this mutation in diabetes mellitus similarly wide variety was detected as well. We conclude that the study design has a huge impact on the result of the genetic epidemiological investigation analyzing the mutation frequency of the A3243G mutation due to the broad clinical phenotype and the different mutation load in different tissues.
Collapse
|
15
|
Zhang S, Tong AL, Zhang Y, Nie M, Li YX, Wang H. Heteroplasmy level of the mitochondrial tRNaLeu(UUR) A3243G mutation in a Chinese family is positively associated with earlier age-of-onset and increasing severity of diabetes. ACTA ACUST UNITED AC 2009; 24:20-5. [PMID: 19382419 DOI: 10.1016/s1001-9294(09)60053-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To investigate the mutations of mitochondrial genome in a pedigree with suspected maternally inherited diabetes and deafness and to explore the correlations between the mutations and clinical features. METHODS Genomic DNA was isolated from blood leucocytes of each member of the pedigree. The mitochondrial genome was amplified with 24-pair primers that could cover the entire mitochondrial DNA. Direct sequencing of PCR products was used to identify any mitochondrial DNA mutations. RESULTS Family members on the maternal side all harbored the tRNALeu(UUR) A3243G mutation. The paternal side family members did not have the mutation. The age-of-onset of diabetes of the 4 maternal side family members was 15, 41, 44, and 65 years old, and their corresponding heteroplasmy level of the mutation was 34.5%, 14.9%, 14.6%, and 5.9%, respectively. The age-of-onset of diabetes and heteroplasmy level of A3243G mutation were negatively correlated with a correlation coefficient of -0.980 (P = 0.02). Meanwhile, patient with high heteroplasmy level of A3243G mutation had relatively low severity of disease. Moreover, 6 reported polymorphisms and 2 new variants were found. CONCLUSIONS The main cause of diabetes in this pedigree is the tRNALeu(UUR) A3243G mutation. However, other gene variants may contribute to its pathogenicity. The heteroplasmy level of the tRNALeu(UUR) A3243G mutation is positively associated with earlier age-of-onset and increasing severity of diabetes.
Collapse
Affiliation(s)
- Shi Zhang
- Department of Endocrinology, Key Laboratory of Endocrinology of Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | | | | | | | | | | |
Collapse
|
16
|
Bibliography. Current world literature. Neuro-muscular diseases: nerve. Curr Opin Neurol 2007; 20:600-4. [PMID: 17885452 DOI: 10.1097/wco.0b013e3282efeb3b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|