[Molecular scanning of candidate mtDNA gene fragment in diabetic pedigrees].
OBJECTIVE
To explore novel pathogenic mutation in the mitochondrial DNA gene in diabetic pedigree.


METHODS
Twenty-eight suspected mitochondrial DNA diabetic families were recruited. The gene fragment was produced by PCR, and mutation was detected by direct sequencing.


RESULTS
In one pedigree, the proband and her mother were found carrying the most common nt3243 A --> G mutation and another 16S rRNA 3205C --> T mutation. But only 3205C --> T was found in her affected brother. All the two patients were deaf and developed diabetes in early age, characterized by impaired beta cell function and low body mass index (BMI). The proband had relatively higher lactic acid concentration than normal individuals. A novel ND1 gene 3434 A --> G(TAT --> TGT) mutation was explored in another proband with deafness and her affected family members.


CONCLUSIONS
16SrRNA 3205C --> T mutation was found in a mitochondrial diabetes mellitus pedigree, implying its potential pathogenic role in diabetes. Another novel ND1 3434 A --> G mutation was found in another diabetic pedigree. Because this mutation causes amino acid change (Tyr --> Cys) and is co-segregated with diabetes, it may be diabetogenic.
Ren
Yan
Y
Endocrine Division, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041 PR China. renyan22@msn.com
Li
Xiu-jun
XJ
Tian
Hao-ming
HM
Liang
Jin-zhong
JZ
Han
Ling-chuan
LC
Zang
Xiang-xun
XX
Yu
Hong-lin
HL
Yu
Ye-rong
YR
Liu
Rui
R
Zhao
Gui-zhi
GZ
Wang
Jia-nan
JN
D000328:Adult; D044466:Asian People / Q000235:genetics; D004252:DNA Mutational Analysis; D004272:DNA, Mitochondrial / Q000235:genetics*; D003920:Diabetes Mellitus / Q000235:genetics*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D010375:Pedigree; D012336:RNA, Ribosomal, 16S / Q000032:analysis / Q000235:genetics*
D004272:DNA, Mitochondrial; D012336:RNA, Ribosomal, 16S