Screening of six polymorphisms related with folate metabolism in parents of individuals with Down syndrome.

Objective: The study aim to investigate C677T, A1298C, A80G, A2756G, 844ins68, A66G polymorphisms in Down syndrome (DS) parents.

Methods: Polymorphisms were evaluated in 35 mothers and 24 fathers of individuals with free trisomy of chromosome 21 confirmed by karyotype. The control group included 26 mothers and 26 fathers who had no children with DS. The molecular analysis was performed by polymerase chain reaction and restriction fragment length polymorphism (reaction chain polymerase restriction fragment length polymorphism) or polymerase chain reaction. The χ test (chi-square) was used to compare allele's differences among the study and the control group. Hardy-Weinberg equilibrium model was performed by χ testing. Multiple logistic regression models and binary logistic regression used to determine the association between polymorphisms and parental DS risk.

Results: This study did not reveal any significant difference in frequencies of polymorphisms. The haplotype analysis did not reveal linkage disequilibrium. The logistic regression analysis did not demonstrate differences between the groups. However, the binary logistic regression showed a higher frequency of the polymorphic homozygote genotype in DS parent group to codominant and dominant model in the RFC1 A80G.

Conclusion: In conclusion, although the screening results were significant only to the RFC1 A80G polymorphism, the other determinations of the genetic factors associated with abnormal chromosome segregation could be helpful in future studies, including other polymorphisms involved in folate metabolism.