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Noskova, A.

Publications and source records attributed to Noskova, A..

2 recordsLinked to original sources

Deletion of porcine BOLL causes defective acrosomes and subfertility in Yorkshire boars

A recessively inherited sperm defect of Finnish Yorkshire boars was detected more than a decade ago. Affected boars produce ejaculates that contain many spermatozoa with defective acrosomes resulting in low fertility and small litters. The acrosome defect was mapped to porcine chromosome 15 but the causal mutation has not been identified. We re-analyzed microarray-derived genotypes of affected boars and performed a haplotype-based association study. Our results confirmed that the acrosome defect maps to a 12.24 Mb segment of porcine chromosome 15 (P=3.38 x 10-14). In order to detect the mutation causing defective acrosomes, we sequenced the genomes of two affected and three unaffected boars to an average coverage of 11-fold. Read-depth analysis revealed a 55 kb deletion that segregates with the acrosome defect. The deletion encompasses the BOLL gene encoding the boule homolog, RNA binding protein which is an evolutionarily highly conserved member of the DAZ (deleted in azoospermia) gene family. Lack of BOLL expression causes spermatogenic arrest and sperm maturation failure in many species. Our study reveals that absence of BOLL is associated with a sperm defect also in pigs. The acrosomes of boars that carry the deletion in the homozygous state are defective suggesting that lack of porcine BOLL compromises acrosome formation. Our findings warrant further research to investigate the precise function of BOLL during spermatogenesis and sperm maturation in pigs.

genomics

A 63-bp insertion in exon 2 of the porcine KIF21A gene is associated with arthrogryposis multiplex congenita

Arthrogryposis multiplex congenita (AMC) is a recessively inherited fatal disease detected almost 20 years ago in the Swiss Large White pig population. A diagnostic marker test enabled the identification of carrier animals, but the underlying causal mutation remains unknown. To identify the mutation underlying AMC, we collected whole-genome genotyping and sequencing data for 11 affected piglets and 23 healthy pigs. Haplotype-based case-control association testing using 47,829 SNPs confirmed that AMC maps to SSC5 (P = 9.4 x10-13). Subsequent autozygosity mapping revealed a common 6.06 Mb region (from 66,757,970 to 72,815,151 bp) of extended homozygosity in 11 piglets affected by AMC. We detected a 63-bp insertion in the second exon of KIF21A gene encoding Kinesin Family Member 21A using whole-genome sequences of a carrier boar, two of its affected and two heterozygous piglets. This insertion was compatible with the recessive inheritance of AMC. The 63-bp insertion likely represents a loss-of-function allele because it is predicted to introduce a premature stop codon in KIF21A gene (p.Val41_Phe42insTer) that truncates 1,614 amino acids ([~] 97%) from the protein. Lack of KIF21A protein is lethal in mice, thus providing additional evidence that a loss-of function allele of KIF21A might cause fatal AMC in pigs. We found that this deleterious allele still segregates at low frequency in the Swiss Large White pig population. The unambiguous detection of carrier animals can now facilitate the eradication of the deleterious allele from the population.

genomics