Diabetes in Hong Kong Chinese - Evidence for familial clustering and parental effects

OBJECTIVE - To investigate transmission patterns of diabetes and their relationships with clinical characteristics in Hong Kong Chinese patients with late-onset (age greater than or equal to 35 years) type 2 diabetes. RESEARCH DESIGN AND METHODS - This study involved 2,310 patients consecutively selected from a hospital clinic-based diabetes registry These patients all reported the diabetes status of their parents as well as siblings. RESULTS - Approximately 36% of the 2,310 patients reported at least 1 affected parent or sibling (25 and 21% reported at least 1 diabetic parent and sibling, respectively). These patients, irrespective of their sex, were more likely to have a diabetic mother than a diabetic father (17 vs. 13% of the male patients and 18 vs. 9% of the female patients, P < 0.01). The male patients were more likely than the female patients to have a diabetic father (13 vs. 9%, P < 0.01). The female patients with a diabetic mother were found to have higher levels of plasma total cholesterol compared with the female patients with a diabetic father in multiple comparisons with adjustment for significance (5.56 +/- 1.30 vs. 5.09 +/- 0.95 mmol/l, P < 0.05). In 2-group comparisons, there was also evidence that the male patients with a diabetic father had higher BMI values than the male patients with a diabetic mother (25.9 +/- 3.5 vs. 25.0 +/- 3.5 kg/m(2), P < 0.05). CONCLUSIONS - We found familial clustering of diabetes in the Hong Kong Chinese population as well as a significant maternal influence and a male sex-specific paternal effect. We suggest that both maternal and paternal factors may be implicated in the development of type 2 diabetes in the Chinese population.