Sperm, short tail (ARMC3-related)

Gene: ARM3C

Transmission: Autosomal recessive

For an autosomal recessive genetic disease an animal must have two copies of the mutation in question to be at risk of developing the disease.  Both parents of an affected animal must be carriers of at least one copy of the mutation.  Animals that have only one copy of the mutation are not at risk of developing the disease but are carrier animals that can pass the mutation on to future generations.

Mutation: Deletion, ARM3C gene: c.1442 delG, p.(Ala451 frameshift STOP 26), exon11, Chr.13.

Medical system: Reproduction

Breed: Swedish Red

Age of onset of symptoms: By puberty

Three related Swedish Red Cattle bulls in an artificial insemination center had reduced sperm count and immobile sperm.  Sperm cells displayed a severe flagellar morphological defect with tails being short, rudimentary (less than 5% normal length) or completely absent.  In particular, the sperm tail was missing the midpiece containing the mitochondria.  Abnormal sperm heads were seen in about half of sperm cells.  Molecular studies identified a mutation in the ARMC3 gene as the plausible cause of the morphological sperm defect.  In the mouse, the ARMC3 is expressed in the testes and is important for flagellar mobility. In a survey of 97 Swedish Red insemination bulls, 23 were heterozygous for the ARM3C mutation, giving a carrier frequency of 23.7%.  A DNA test will allow insemination centers to evaluate their animals to eliminate this mutation from their animals.

References:

OMIA link: [1334-9913]

Pausch H, Venhoranta H, Wurmser C, et al. (2016) A frameshift mutation in ARMC3 is associated with a tail stump sperm defect in Swedish Red (Bos taurus) cattle. BMC Genet 17:49.  [pm/26923438]

With contributions by: Juliette Beaumier and Anaïs Robert, Class of 2030, Faculty of Veterinary Medicine, University of Montreal.  (Translation: DWS).