Linkage analysis of the genetic markers of the candidate genes with non-insulin dependent diabetes mellitus in Chinese families.
OBJECTIVE
To explore the relationship between the genetic markers of the candidate genes (insulin receptor, glucose transporter 2 and glucokinase) and non-insulin dependent diabetes mellitus (NIDDM) in Chinese pedigrees.


METHODS
Genomic DNA of 87 members in 12 Chinese NIDDM pedigrees was amplified using PCR technique. Denaturing polyacrylamide gel electrophoresis was applied to detect short tandem repeat polymorphisms. The linkage program was used under the models of autosomal dominant and recessive. The individuals with impaired glucose tolerance (IGT) of age < or = 45 and age > 45 were counted as affected and unknown status respectively.


RESULTS
Linkage of insulin receptor gene and NIDDM was strongly and significantly rejected with total LOD score of-infinity (theta = 0.000). Linkage analysis of glucose transporter 2 gave the result with total LOD score of 2.646 (theta = 0.000) in 4 pedigrees. Linkage of glucokinase and NIDDM was of significance with total LOD score reaching 3.150 in the integration of 6 pedigrees.


CONCLUSIONS
Mutations in or near the insulin receptor gene are unlikely to be the major cause of inherited predisposition to NIDDM in Chinese pedigrees that are related in this study, not excluding the principal role in the other Chinese or populations, while the mutations/variations near or at the glucose transporter 2 gene locus might be something of the cause, which needs more data to be ascertained, of familial NIDDM in Chinese pedigrees. However, the variations in or near the glucokinase gene might play a dominant role in the development of NIDDM in some Chinese and represent a subgroup of common NIDDM.
Ma
L
L
Department of Endocrinology, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China.
Wang
H
H
Chen
J
J
He
R
R
Wu
X
X
Chai
J
J
D000328:Adult; D044466:Asian People; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics*; D005260:Female; D008040:Genetic Linkage; D005819:Genetic Markers / Q000235:genetics; D018149:Glucose Intolerance / Q000235:genetics*; D006801:Humans; D008126:Lod Score; D008297:Male; D008875:Middle Aged
D005819:Genetic Markers