We investigated alterations of serum levels of Lp(a) and lipid profiles in type 2 diabetic patients and their normoglycemic first-degree relatives to evaluate the potential genetic association among these subjects. Serum Lp(a), triglycerride (TG), total cholesterol (TC), high density lipoprotein-cholesterol (HDL-C), and low density lipoprotein (LDL-C) levels were analyzed in 62 type 2 diabetic patients and 67 normoglycemic first-degree relatives from 29 type 2 diabetic pedigrees, and 45 healthy controls without family histories of diabetes. Dyslipidemia was observed in diabetics and their normoglycemic first-degree relatives. While higher serum TG levels were observed in both type 2 diabetics and their first-degree relatives than those in controls, higher TG levels in diabetics were found when compared with those in first-degree relatives. Meanwhile, lower serum HDL-C levels were observed in both type 2 diabetic patients and their first-degree relatives than those in controls. No significant difference of serum TC and LDL-C levels was found among the three groups. On the other hand, we did not observe significant differences of serum Lp(a) levels between type 2 diabetic patients and normoglycemic first-degree relatives, nor were any significant differences observed between diabetic patients and healthy controls (24.6+/-19.9 vs. 25.8+/-21.2, and 21.3+/-20.5 mg/dl). Although the average serum Lp(a) levels were similar in all subgroups, we did observe a positive correlation of Lp(a) between type 2 diabetic patients and their offspring (r=0.448, P<0.01), suggesting a potential genetic control for Lp(a) levels in type 2 diabetics families.