title: Expansion of the HSFY gene family in pig lineages : HSFY expansion in suids.
abstract: BACKGROUND
  Amplified gene families on sex chromosomes can harbour genes with important biological functions, especially relating to fertility. The Y-linked heat shock transcription factor (HSFY) family has become amplified on the Y chromosome of the domestic pig (Sus scrofa), in an apparently independent event to an HSFY expansion on the Y chromosome of cattle (Bos taurus). Although the biological functions of HSFY genes are poorly understood, they appear to be involved in gametogenesis in a number of mammalian species, and, in cattle, HSFY gene copy number may correlate with levels of fertility.
  
  
  RESULTS
  We have investigated the HSFY family in domestic pig, and other suid species including warthog, bushpig, babirusa and peccaries. The domestic pig contains at least two amplified variants of HSFY, distinguished predominantly by presence or absence of a SINE within the intron. Both these variants are expressed in testis, and both are present in approximately 50 copies each in a single cluster on the short arm of the Y. The longer form has multiple nonsense mutations rendering it likely non-functional, but many of the shorter forms still have coding potential. Other suid species also have these two variants of HSFY, and estimates of copy number suggest the HSFY family may have amplified independently twice during suid evolution.
  
  
  CONCLUSIONS
  The HSFY genes have become amplified in multiple species lineages independently. HSFY is predominantly expressed in testis in domestic pig, a pattern conserved with cattle, in which HSFY may play a role in fertility. Further investigation of the potential associations of HSFY with fertility and testis development may be of agricultural interest.
authors.affiliation: Department of Pathology, University of Cambridge, Cambridge, CB2 1QP, UK. bms41@cam.ac.uk.
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Skinner
authors.affiliation: Department of Pathology, University of Cambridge, Cambridge, CB2 1QP, UK. kg206@cam.ac.uk.
authors.forename: Kim
authors.initials: K
authors.lastname: Lachani
authors.affiliation: Department of Pathology, University of Cambridge, Cambridge, CB2 1QP, UK. cas1001@cam.ac.uk.
authors.forename: Carole A
authors.initials: CA
authors.lastname: Sargent
authors.affiliation: Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK. fy1@sanger.ac.uk.
authors.forename: Fengtang
authors.initials: F
authors.lastname: Yang
authors.affiliation: Department of Pathology, University of Cambridge, Cambridge, CB2 1QP, UK. P.J.I.Ellis@kent.ac.uk.|Present addresses: School of Biosciences, University of Kent, Canterbury, CT2 7NJ, UK. P.J.I.Ellis@kent.ac.uk.
authors.forename: Peter
authors.initials: P
authors.lastname: Ellis
authors.affiliation: Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK. th2@sanger.ac.uk.
authors.forename: Toby
authors.initials: T
authors.lastname: Hunt
authors.affiliation: Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK. bf2@sanger.ac.uk.
authors.forename: Beiyuan
authors.initials: B
authors.lastname: Fu
authors.affiliation: Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK. sg14@sanger.ac.uk.
authors.forename: Sandra
authors.initials: S
authors.lastname: Louzada
authors.affiliation: Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK. cc770@medschl.cam.ac.uk.|Present addresses: School of Clinical Medicine, University of Cambridge, Cambridge, CB2 0SP, UK. cc770@medschl.cam.ac.uk.
authors.forename: Carol
authors.initials: C
authors.lastname: Churcher
authors.affiliation: Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK. cts@sanger.ac.uk.
authors.forename: Chris
authors.initials: C
authors.lastname: Tyler-Smith
authors.affiliation: Department of Pathology, University of Cambridge, Cambridge, CB2 1QP, UK. na106@cam.ac.uk.
authors.forename: Nabeel A
authors.initials: NA
authors.lastname: Affara
mesh_terms: D000818:Animals; D018389:Codon, Nonsense; D042622:DNA Repeat Expansion; D005784:Gene Amplification; D008297:Male; D005810:Multigene Family; D020086:Short Interspersed Nucleotide Elements; D034421:Sus scrofa; D013552:Swine / Q000145:classification / Q000235:genetics*; D013737:Testis / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014998:Y Chromosome / Q000235:genetics*
chemical_list: D018389:Codon, Nonsense; D014157:Transcription Factors