Human Genome

Nature 409, 951-953 (15 February 2001) | doi:10.1038/35057185; Received 27 October 2000; Accepted 8 December 2000

Comparison of human genetic and sequence-based physical maps

Adong Yu1, Chengfeng Zhao1, Ying Fan1, Wonhee Jang2, Andrew J. Mungall3, Panos Deloukas3, Anne Olsen4, Norman A. Doggett5, Nader Ghebranious1, Karl W. Broman6 & James L. Weber1

Recombination is the exchange of information between two homologous chromosomes during meiosis. The rate of recombination per nucleotide, which profoundly affects the evolution of chromosomal segments, is calculated by comparing genetic and physical maps. Human physical maps have been constructed using cytogenetics1, overlapping DNA clones2 and radiation hybrids3; but the ultimate and by far the most accurate physical map is the actual nucleotide sequence. The completion of the draft human genomic sequence4 provides us with the best opportunity yet to compare the genetic and physical maps. Here we describe our estimates of female, male and sex-average recombination rates for about 60% of the genome. Recombination rates varied greatly along each chromosome, from 0 to at least 9 centiMorgans per megabase (cM Mb-1). Among several sequence and marker parameters tested, only relative marker position along the metacentric chromosomes in males correlated strongly with recombination rate. We identified several chromosomal regions up to 6 Mb in length with particularly low (deserts) or high (jungles) recombination rates. Linkage disequilibrium was much more common and extended for greater distances in the deserts than in the jungles.

  1. Center for Medical Genetics, Marshfield Medical Research Foundation, Marshfield, Wisconsin 54449, USA
  2. National Center for Biotechnology Information, National Institutes of Health, Bethesda, Maryland 20894, USA
  3. The Sanger Centre, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK
  4. Joint Genome Institute, Walnut Creek, California 94598, USA
  5. Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
  6. Department of Biostatistics, Johns Hopkins University, Baltimore, Maryland 21205-2179, USA

Correspondence to: James L. Weber1 Correspondence and requests for materials should be addressed to J.L.W. (e-mail: Email: