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Publisher Copyright: © 2020 by the authors. Licensee MDPI, Basel, Switzerland. A variety of cat breeds have been developed via novelty selection on aesthetic, dermatological traits, such as coat colors and fur types. A recently developed breed, the lykoi (a.k.a. werewolf cat), was bred from cats with a sparse hair coat with roaning, implying full color and all white hairs. The lykoi phenotype is a form of hypotrichia, presenting as a significant reduction in the average numbers of follicles per hair follicle group as compared to domestic shorthair cats, a mild to severe perifollicular to mural lymphocytic infiltration in 77% of observed hair follicle groups, and the follicles are often miniaturized, dilated, and dysplastic. Whole genome sequencing was conducted on a single lykoi cat that was a cross between two independently ascertained lineages. Comparison to the 99 Lives dataset of 194 non‐lykoi cats suggested two variants in the cat homolog for Hairless (HR) (HR lysine demethylase and nuclear receptor corepressor) as candidate causal gene variants. The lykoi cat was a compound heterozygote for two loss of function variants in HR, an exon 3 c.1255_1256dupGT (chrB1:36040783), which should produce a stop codon at amino acid 420 (p.Gln420Serfs*100) and, an exon 18 c.3389insGACA (chrB1:36051555), which should produce a stop codon at amino acid position 1130 (p.Ser1130Argfs*29). Ascertainment of 14 additional cats from founder lineages from Canada, France and different areas of the USA identified four additional loss of function HR variants likely causing the highly similar phenotypic hair coat across the diverse cats. The novel variants in HR for cat hypotrichia can now be established between minor differences in the phenotypic presentations.

Publisher Copyright: © 2020 by the authors. An inherited neurologic syndrome in a family of mixed-breed Oriental cats has been characterized as forebrain commissural malformation, concurrent with ventriculomegaly and interhemispheric cysts. However, the genetic basis for this autosomal recessive syndrome in cats is unknown. Forty-three cats were genotyped on the Illumina Infinium Feline 63K iSelect DNA Array and used for analyses. Genome-wide association studies, including a sib-transmission disequilibrium test and a case-control association analysis, and homozygosity mapping, identified a critical region on cat chromosome A3. Short-read whole genome sequencing was completed for a cat trio segregating with the syndrome. A homozygous 7 bp deletion in growth differentiation factor 7 (GDF7) (c.221_227delGCCGCGC [p.Arg74Profs]) was identified in affected cats, by comparison to the 99 Lives Cat variant dataset, validated using Sanger sequencing and genotyped by fragment analyses. This variant was not identified in 192 unaffected cats in the 99 Lives dataset. The variant segregated concordantly in an extended pedigree. In mice, GDF7 mRNA is expressed within the roof plate when commissural axons initiate ventrally-directed growth. This finding emphasized the importance of GDF7 in the neurodevelopmental process in the mammalian brain. A genetic test can be developed for use by cat breeders to eradicate this variant.

International audience; The AdaptMap project investigates worldwide goat diversity with a focus on domestication, adaptation associated with local environmental conditions, and adaptation in response to selection for production systems. The ultimate goal of the project is to enable sustainable goat breeding by leveraging the use of genomic information. During the first phase of AdaptMap, several analyses were performed to characterize population genetics and history, to identify selection signatures and signals of environmental adaptation through landscape genomics, and to devise a panel of SNPs for parentage assessment. Overall, our results showed a close association between the distribution of diversity and geography, with a clear partitioning of the populations into groups according to the continental origin. The 3 major gene pools corresponded to goats from Europe, Africa and western Asia, a pattern consistent with the recognized paths of human migration out of the Fertile Crescent. Within these major pools, further patterns of variation mirrored geographical sub-structuring, human history and animal husbandry practices. Comparing the European and African gene pools, European breeds tended to be more discreet, in line with the practice of creating breeds through active human-controlled genetic isolation, while greater gene flow was observed in Africa. Among the observed “hotspots” of runs of homozygosity, some were unique across continental groups. The results of selection signature analysis were generally consistent with previous evidence from independent studies. Signals of adaptation to the environment were also identified, showing the strongest association with differences in mean annual temperature. Finally, a highly informative marker panel for parentage assessment was developed to assist breeding in goat populations worldwide. Taken together, our evidence outlines a remarkable diversity occurring at the global scale, locally partitioned and often affected by introgression from cosmopolitan breeds. This provides a useful framework to direct improvement and conservation actions, and to select breeding targets. After excluding under-performing samples and markers, 970 targeted markers with 50X sequence coverage or greater and an overall average call rate of 98% were included in the data set. Furthermore, novel genetic mutations identified in these important targeted regions were characterized. Data from this panel can be used to identify known causative mutations, improve pedigree accuracy and assist in genetic selection for the sheep industry at a cost of US$15. The application of this cost-effective sheep genomics marker panel can be used to promote improved production, animal health and profitability of the US sheep industry.