Objective. To study the associations of IDDM3

IDDM4

IDDM5 and IDDM8 with insulin- dependent diabetes mellitus （IDDM）. Methods. The polymorphisms of short tandem repeat （STR） loci D15S657

D11S1369

D6S2420 and D6S503

linked to IDDM3

IDDM4

IDDM5 and IDDM8 respectively

were studied by polymerase chain reaction and polyacrylamide gel electrophoresis （PCR- PAGE） followed by direct sequencing of PCR products in 105 normal Chinese Han nationality subjects and 48 patients with IDDM. Results. The allele frequencies of allele A5 at D15S657 locus

allele A5 at D11S1369 locus and allele A4 at D6S2420 locus were increased significantly in patients with IDDM compared to those in the control group. No difference in the allele frequencies at D6S503 locus was observed between IDDM and control group. Conclusion. IDDM3

IDDM4

IDDM5 but not IDDM8 may be associated with IDDM in Chinese Han nationality population.