Non-crossover gene conversions show strong GC bias and unexpected clustering in humans.
Although the past decade has seen tremendous progress in our understanding of fine-scale recombination, little is known about non-crossover (NCO) gene conversion. We report the first genome-wide study of NCO events in humans. Using SNP array data from 98 meioses, we identified 103 sites affected by NCO, of which 50/52 were confirmed in sequence data. Overlap with double strand break (DSB) hotspots indicates that most of the events are likely of meiotic origin. We estimate that a site is involved in a NCO at a rate of 5.9 × 10(-6)/bp/generation, consistent with sperm-typing studies, and infer that tract lengths span at least an order of magnitude. Observed NCO events show strong allelic bias at heterozygous AT/GC SNPs, with 68% (58-78%) transmitting GC alleles (p = 5 × 10(-4)). Strikingly, in 4 of 15 regions with resequencing data, multiple disjoint NCO tracts cluster in close proximity (∼20-30 kb), a phenomenon not previously seen in mammals.
|Year of Publication||
2015 Mar 25
|PubMed Central ID||
U01 DK085501 / DK / NIDDK NIH HHS / United States
GM83098 / GM / NIGMS NIH HHS / United States
U01 DK085524 / DK / NIDDK NIH HHS / United States
U01 DK085545 / DK / NIDDK NIH HHS / United States
R01 GM100233 / GM / NIGMS NIH HHS / United States
F32 HG005944 / HG / NHGRI NIH HHS / United States
U01 DK085526 / DK / NIDDK NIH HHS / United States
U01 DK085584 / DK / NIDDK NIH HHS / United States
Howard Hughes Medical Institute / United States
R01 GM083098 / GM / NIGMS NIH HHS / United States