Genetic Analysis of Variation in Human Meiotic Recombination Jaboa Lake Bio 5 23 February 2010 Chowdhury, Reshmi, Philippe R.J. Boise, Eleanor Feingold, Stephanie L. Sherman, and Vivian G. Cheung. "Genetic Analysis of Variation in Human Meiotic Recombination." PloS Genetics. 5.9 (2009): 1-10. Print.
Keywords Gene – a portion of DNA that determines a single protein Meiosis – a type of cell division where the chromosome number is reduced from diploid to haploid (creates four haploid cells) SNP Genotype – (Single Nucleotide Polymorphism) a type of genetic variation Loci – the location of a gene sequence in a chromosome Genotype – organism’s hereditary makeup Meiotic Recombination – needed for cell division and generates genetic diversity. It provides daughter cells with allelic compositions that differ from those of their parents
Hypothesis Recombination frequency differs significantly between females and males, and also among individuals within each gender . Errors in meiotic recombination causes chromosomal abnormalities so cellular processes have to make sure meiotic recombination occurs properly. Causes in which DNA breaks in meioses that resolve into crossovers are unknown. The variation in recombination rates offers an opportunity to identify regulators involved in the process
Hypothesis Meiotic recombination is needed to form human gametes and is very important in creating genetic diversity, so it is expected that the number and location of exchanges are regulated, but studies show significant gender and interindividual variation in genome-wide recombination rates.
Methods By treating recombination rate as a quantitative trait, the genome for DNA variants that influence this process can be screened Genotypes were used from SNPmarkers with high densities from 2,315 individuals and their children to identify genetic variants that influence the number of meiotic recombination events per gameteby doing a genome-wide association study.
Results Six genetic loci were identified that show allelic association with female and male recombination phenotypes. Among them are the sequence variants on chromosome 17q21.31 and those in RNF212 that were earlier reported to be associated with recombination phenotypes in females and males. The other four loci were not known to contribute to individual variation in genome-wide recombination rates. Three loci that influence female recombination and three different loci that influence male recombination were found Each identified locus explained only a small amount of variance, which was about 10%of the variation in each gender recombination phenotype
Discussion The results gave new information to use to study meiotic recombination regulation Results suggest that gender differences in recombination result from differences in the genetic regulation of female and male meiosis. Suggested that there was a mechanism for variability in recombination that is needed for genetic diversity and proper chromosome segregation