|Smith, Timothy - Tim|
Submitted to: Plant and Animal Genome VX Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 1/1/1998
Publication Date: N/A
Technical Abstract: We identified previously the existence of heterogeneity in recombination rate (theta) between two bulls in the DYA-PRL interval on BTA23 (Park et al., Genomics 27:113). To further characterize the region, a total of 1628 sperm from 5 different bulls (4 breeds) of similar age were evaluated for (theta) in the two adjacent intervals DYA-DRB3 and DRB3-PRL. Significant variation in (theta) was found in both intervals. The variatio in (theta) was individual- and region-specific. Using a meiotic breakpoint strategy combined with whole genome amplification (PEP) and sperm typing we reduced the region of variation into a smaller interval between D23S22- D23S23 (ranged 4.5%-11.9% among 5 bulls). To estimate the actual physical distance and to identify the putative DNA sequences responsible for variation in (theta), a partial YAC contig was constructed for the D23S22- D23S23 interval. Primary screening of a YAC library yielded 14 YAC clones (sized from 390-2700 kb). For all YACs, YAC-end sequence rescue by inverse or vectorette PCR was used to develop 23 new STSs. All YAC ends were mapped using a somatic cell hybrid panel. The percentage of chimerism in this region was high (62%) in contrast to the previous estimate of 22% for this library, suggesting unusual recombination activity. Gene order between D23S22-D23S23 was determined on the basis of information from the contig: D23S23-D23S36-D23S7-VEGF-D23S22. To precisely estimate the physical size of the interval and the molecular basis of variation, additional YACs and/or BACs will be necessary to complete the contig.