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Evolution of the AZFc Region in Primates

  1. Yueh-Hsiang Yu,
  2. Pauline H Yen

Published Online: 15 SEP 2009

DOI: 10.1002/9780470015902.a0021967

eLS

eLS

How to Cite

Yu, Y.-H. and Yen, P. H. 2009. Evolution of the AZFc Region in Primates. eLS. .

Author Information

  1. Graduate Institute of Life Sciences, National Defense Medical Center, Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan

Publication History

  1. Published Online: 15 SEP 2009

Abstract

The Azoospermia Factor c (AZFc) region on the human Y chromosome is one of the most polymorphic regions in the human genome. It encodes several gene families with germ-cell specific expression and is frequently deleted in infertile men with very low sperm counts or no sperm. AZFc consists mainly of very long repeats (amplicons) that have different evolutionary histories. Some of the ampliconic sequences are remnants of the ancient Y chromosome and share homology with the X chromosome. Other sequences arrived on the Y chromosome through segmental duplication and transposition of autosomal sequences or through messenger ribonucleic acid (mRNA) retroposition. Subsequent rearrangements such as duplication, inversion and intragenic amplification result in the various structures found on the Y chromosomes of today's primates.

Key Concepts

  • The AZFc region on the human Y chromosome contains several testis-specific gene families and is essential for normal spermatogenesis.

  • The AZFc region consists mainly of large amplicons and is prone to rearrangement such as deletion, duplication and inversion.

  • Some ampliconic sequences are remnants of the ancestral Y chromosome and retain sequence similarity with the X chromosome.

  • Other AZFc sequences arrived on the Y chromosome at various time during primate evolution through duplication and transposition of autosomal sequences.

  • The CDY gene within the yellow amplicon arose from retroposition of an ancient autosomal CDYL gene and contains no introns.

Keywords:

  • Y chromosome;
  • AZFc;
  • segmental duplication;
  • primate evolution