Determination of the frequency of Alu insertion the inMUTYH gene in healthy individuals

Guanine is modified to 8-hydroxy-2-deoxyguanosine (8OHdG) by the effect of oxidative stres. MUTYH encodes a glycosylase ezyme which has role in the repair of this damage and to protect the genome from the mutagenic effects of 8OHdG. It is thought that the insertion of Alu element to the 15th intronic region of MUTYH gene could interrupt BER DNA repair mechanism and consequently result in accumulation of 8OHdG in genomic DNA by changing the structure and function of the gene. The individuals included in the study were divided into groups according to their age. Of 309 individuals 140 (45.3%) were genotyped as homozgous negative for insertion (-/-), 80 (25.9%) were genotyped as heterozygous (+/-) and 89 (28.8%) were genotyped as homozygous positive for insertion (+/+). The association of genotype distribution and sex was tested and no statistically significant difference was found, but significant difference was observed in the association of genotype distribution and age. When the genotype distribution in different age groups are compared in men and women seperately, significant differences were determined in each group. The highest frequency of insertion psitive genotype (+/+) was observed in 50-59 age group in both women (46.7%) and men (36.4%).