Paralogy mapping: identification of a region in the human MHC triplicated onto human chromosomes 1 and 9 allows the prediction and isolation of novel PBX and NOTCH loci

Genomics. 1996 Jul 1;35(1):101-8. doi: 10.1006/geno.1996.0328.


The human genome contains a group of gene families whose members map within the same regions of chromosomes 1, 6, and 9. The number of gene families involved and their pronounced clustering to the same areas of the genome indicate that their mapping relationship is nonrandom. By combining mapping data and sequence information for the gene families, we have determined that these sequences are part of a large region that spans several megabases. This region is present in three copies: on the long arm of human chromosome 1, the short arm of chromosome 6, and the long arm of chromosome 9. We have characterized the phylogenesis of two of the gene families involved and propose an evolutionary route for the creation of the three regions. Our analysis led us to predict and demonstrate the presence of two loci, a PBX locus on chromosome 6 and a NOTCH locus on chromosome 1. The discovery of this triplicated region increases our understanding of the evolution of the human genome and may have considerable practical implications for gene mapping prediction and novel approaches to isolating new gene family members and uncloned disease loci.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Chromosome Mapping / methods*
  • Chromosomes, Human, Pair 1 / genetics*
  • Chromosomes, Human, Pair 6 / genetics*
  • Chromosomes, Human, Pair 9 / genetics*
  • DNA-Binding Proteins / classification
  • DNA-Binding Proteins / genetics*
  • Evolution, Molecular
  • Gene Library
  • Humans
  • Insecta / genetics
  • Mammals / genetics
  • Membrane Proteins / classification
  • Membrane Proteins / genetics*
  • Mice / genetics
  • Molecular Sequence Data
  • Multigene Family*
  • Phylogeny
  • Pre-B-Cell Leukemia Transcription Factor 1
  • Proto-Oncogene Proteins / classification
  • Proto-Oncogene Proteins / genetics*
  • Receptors, Notch
  • Sequence Alignment
  • Sequence Homology, Nucleic Acid
  • Vertebrates / genetics


  • DNA-Binding Proteins
  • Membrane Proteins
  • Pre-B-Cell Leukemia Transcription Factor 1
  • Proto-Oncogene Proteins
  • Receptors, Notch
  • PBX1 protein, human

Associated data

  • GENBANK/U50549