Background: There are incon- sistent reports concerning N-acetyltransfer- ase 2 (NAT2) genotypes in diabetes mellitus (DM). Objective: The objective of the study was to explore any association between NAT2 genotypes and Type 1 and Type 2 DM in Jordanians. Methods: 106 Type 1 and 110 Type 2 DM patients attending the "National Center for Diabetes, Endocrinology and Ge- netics", Amman, Jordan, were included in the study. DNA was extracted from venous blood using a commercial DNA extraction kit. NAT2 genotyping was performed using polymerase chain reaction-restriction frag- ment length polymorphism (PCR-RFLP). Results: The frequency of the genotype that encodes rapid acetylation (the wild-type genotype NAT2*4/4) was similar in the two types of diabetes mellitus. Those which en- code intermediate acetylation (NAT2*4/5, NAT2*4/6, and NAT2*4/7) were higher in Type 2 diabetes (0.482) compared to Type 1 diabetes (0.339), while the frequency of genotypes which encode slow acetyla- tion (NAT2*5/5, NAT2*5/6, NAT2*5/7, NAT2*6/6, NAT2*6/7, and NAT2*7/7) were higher in Type 1 diabetes (0.547) compared to Type 2 diabetes (0.418). Conclusion: There is excess of genotypes encoding intermedi- ate acetylation in Type 2 DM and an excess of slow acetylator genotypes in Type 1 DM. Furthermore, NAT2*4/6 genotype (which encodes intermediate acetylation) was more prevalent in Type 2 DM. Type 1 DM behaved similar to non-diabetic controls in regard to acetylation status.
