Abstract
Down syndrome caused by presence of extra chromosome 21 originates from nondisjunction during parental gametogenesis. For overwhelming cases, the error occurs in oocyte and all the nondisjunction events are not stochastic. With increasing number of research efforts, it has come to know that maternal genetic architecture may be considered as risk factors for chromosomal errors. Polymorphisms of the genes involved in chromosome segregation, recombination and folic acid metabolisms have been investigated for their association with Down syndrome child birth. But the results are conflicting owing to ethnic and sociocultural differences. Here, we have discussed and summarized the outcome of the studies conducted on different population sample from different parts of world and tried to figure out the common polymorphisms, which could be used as makers for preconceptional screening of Down syndrome child birth risk among the women.