Unraveling the Genetic Basis of Congenital Sensorineural Deafness in Blue-Eyed White Alpacas

Principal investigator:

Felipe Fegundes de Avila
Veterinary Genetics Laboratory
University of California, Davis
9/01/2019–8/31/22
$20,295

Alpacas are economically important for their highly-valued fleece, which offers a stronger, finer, softer, hypoallergenic, and eco-friendly textile. Alpaca fiber comes in different natural colors, but white fleece is most desirable because it can be easily dyed to produce any color. Therefore, alpaca breeders have traditionally used phenotypic selection to increase the frequency of white individuals in their herds. White alpacas are sometimes born with blue eyes, and approximately 80% of these individuals are deaf. Since alpacas are herd animals, adaption to deafness is possible; nonetheless, many breeders regard this as an undesirable trait, and the Canadian Llama and Alpaca Association consider deafness a congenital disqualifier, prohibiting deaf individuals from being registered. The genetic bases of coat color in alpacas is poorly understood, and contrary to other species (such as dogs, cats, horses, and humans), the genetic underpinnings of deafness in blue-eyed white alpacas remain largely unknown. Here we propose to study the genomes of deaf, blue-eyed white alpacas by high-throughput sequencing and compare those to the genomes of both blue-eyed white non-deaf and non-white, with the goal to discover the causative mutation(s) and develop DNA-based diagnostic tests. The proposed work builds upon the novel study that mapped pigmentation genes to alpaca chromosomes, as well as a recently completed study aimed at improving the alpaca reference genome. Our ultimate goal is to develop genetic tests that will allow owners to make informed breeding decisions when selecting for white coat color and minimizing the production of deaf animals.