Physical and genetic mapping of the human X chromosome centromere: repression of recombination.


Journal Article

Classical genetic studies in Drosophila and yeast have shown that chromosome centromeres have a cis-acting ability to repress meiotic exchange in adjacent DNA. To determine whether a similar phenomenon exists at human centromeres, we measured the rate of meiotic recombination across the centromere of the human X chromosome. We have constructed a long-range physical map of centromeric alpha-satellite DNA (DXZ1) by pulsed-field gel analysis, as well as detailed meiotic maps of the pericentromeric region of the X chromosome in the CEPH family panel. By comparing these two maps, we determined that, in the proximal region of the X chromosome, a genetic distance of 0.57 cM exists between markers that span the centromere and are separated by at least the average 3600 kb physical distance mapped across the DXZ1 array. Therefore, the rate of meiotic exchange across the X chromosome centromere is <1 cM/6300 kb (and perhaps as low as 1 cM/17,000 kb on the basis of other physical mapping data), at least eightfold lower than the average rate of female recombination on the X chromosome and one of the lowest rates of exchange yet observed in the human genome.

Full Text

Cited Authors

  • Mahtani, MM; Willard, HF

Published Date

  • February 1998

Published In

Volume / Issue

  • 8 / 2

Start / End Page

  • 100 - 110

PubMed ID

  • 9477338

Pubmed Central ID

  • 9477338

Electronic International Standard Serial Number (EISSN)

  • 1549-5469

International Standard Serial Number (ISSN)

  • 1088-9051

Digital Object Identifier (DOI)

  • 10.1101/gr.8.2.100


  • eng