high-resolution recombination patterns in a region of human chromosome 21 measured by sperm typing高分辨率的重组模式在人类21号染色体的一个区域来衡量精子打字.pdfVIP

High-Resolution Recombination Patterns in a Region of Human Chromosome 21 Measured by Sperm Typing 1 1 1 2 1* Irene Tiemann-Boege , Peter Calabrese , David M. Cochran , Rebecca Sokol , Norman Arnheim 1 Molecular and Computational Biology Program, University of Southern California, Los Angeles, California, United States of America, 2 Obstetrics, Gynecology and Medicine, and Women’s Hospital, Health Sciences Campus, University of Southern California, Los Angeles, California, United States of America For decades, classical crossover studies and linkage disequilibrium (LD) analysis of genomic regions suggested that human meiotic crossovers may not be randomly distributed along chromosomes but are focused instead in ‘‘hot spots.’’ Recent sperm typing studies provided data at very high resolution and accuracy that defined the physical limits of a number of hot spots. The data were also used to test whether patterns of LD can predict hot spot locations. These sperm typing studies focused on several small regions of the genome already known or suspected of containing a hot spot based on the presence of LD breakdown or previous experimental evidence of hot spot activity. Comparable data on target regions not specifically chosen using these two criteria is lacking but is needed to make an unbiased test of whether LD data alone can accurately predict active hot spots. We used sperm typing to estimate recombination in 17 almost contiguous ;5 kb intervals spanning 103 kb of human Chromosome 21. We found two intervals that contained new hot spots. The comparison of our data with recombination rates predicted by statistical analyses of LD showed that, overall, the two datasets corresponded well, except for one predicted hot spot that showed little crossing over. This study doubles the experimental data on recombination in me