Pseudoautosomal region 1 length polymorphism in the human population

PLoS Genet. 2014 Nov 6;10(11):e1004578. doi: 10.1371/journal.pgen.1004578. eCollection 2014 Nov.


The human sex chromosomes differ in sequence, except for the pseudoautosomal regions (PAR) at the terminus of the short and the long arms, denoted as PAR1 and PAR2. The boundary between PAR1 and the unique X and Y sequences was established during the divergence of the great apes. During a copy number variation screen, we noted a paternally inherited chromosome X duplication in 15 independent families. Subsequent genomic analysis demonstrated that an insertional translocation of X chromosomal sequence into the Y chromosome generates an extended PAR [corrected].The insertion is generated by non-allelic homologous recombination between a 548 bp LTR6B repeat within the Y chromosome PAR1 and a second LTR6B repeat located 105 kb from the PAR boundary on the X chromosome. The identification of the reciprocal deletion on the X chromosome in one family and the occurrence of the variant in different chromosome Y haplogroups demonstrate this is a recurrent genomic rearrangement in the human population. This finding represents a novel mechanism shaping sex chromosomal evolution.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chromosomes / genetics
  • Chromosomes, Human, X / genetics*
  • Chromosomes, Human, Y / genetics*
  • Evolution, Molecular*
  • Haplotypes
  • Hominidae / genetics
  • Homologous Recombination / genetics
  • Humans
  • Polymorphism, Genetic
  • Repetitive Sequences, Nucleic Acid / genetics
  • Translocation, Genetic

Grant support

MAM is a scholarship holder of ES Villigst. MSH is a postdoctoral fellow at KU Leuven supported by F+/12/037. MHDL is postdoctoral fellow of FWO-Vlaanderen. This work was made possible by grants from the KUL PFV/10/016 SymBioSys to JRV and TV and GOA/12/015 to JRV, HVE and KD. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.