A splice variant in KRT71 is associated with curly coat phenotype of Selkirk Rex cats.

One of the salient features of the domestic cat is the aesthetics of its fur. The Selkirk Rex breed is defined by an autosomal dominant woolly rexoid hair (ADWH) abnormality that is characterized by tightly curled hair shafts. A genome-wide case - control association study was conducted using 9 curly coated Selkirk Rex and 29 controls, including straight-coated Selkirk Rex, British Shorthair and Persian, to localize the Selkirk autosomal dominant rexoid locus (SADRE). Although the control cats were from different breed lineages, they share recent breeding histories and were validated as controls by Bayesian clustering, multi-dimensional scaling and genomic inflation. A significant association was found on cat chromosome B4 (Praw = 2.87 × 10(-11)), and a unique haplotype spanning ~600 Kb was found in all the curly coated cats. Direct sequencing of four candidate genes revealed a splice site variant within the KRT71 gene associated with the hair abnormality in Selkirk Rex

Independent DSG4 frameshift variants in cats with hair shaft dystrophy

Investigations of hereditary phenotypes in spontaneous mutants may help to better understand the physiological functions of the altered genes. We investigated two unrelated domestic shorthair cats with bulbous swellings of the hair shafts. The clinical, histopathological, and ultrastructural features were similar to those in mice with lanceolate hair phenotype caused by loss-of-function variants in Dsg4 encoding desmoglein 4. We sequenced the genomes from both affected cats and compared the data of each affected cat to 61 control genomes. A search for private homozygous variants in the DSG4 candidate gene revealed independent frameshift variants in each case, c.76del or p.Ile26fsLeu*4 in case no. 1 and c.1777del or p.His593Thrfs*23 in case no. 2. DSG4 is a transmembrane glycoprotein located primarily in the extracellular part of desmosomes, a complex of adhesion molecules responsible for connecting the keratin intermediate filaments of neighbouring epithelial cells. Desmosomes are essential for normal hair shaft formation. Both identified DSG4 variants in the affected cats lead to premature stop codons and truncate major parts of the open-reading frame. We assume that this leads to a complete loss of DSG4 function, resulting in an incorrect formation of the desmosomes and causing the development of defective hair shafts. Together with the knowledge on the effects of DSG4 variants in other species, our data suggest that the identified DSG4 variants cause the hair shaft dystrophy. To the best of our knowledge, this study represents the first report of pathogenic DSG4 variants in domestic animals

Hypotrichosis with Juvenile Macular Dystrophy

Hypotrichosis with juvenile macular dystrophy is a rare autosomal recessive disease, characterized by hypotrichosis and progressive macular degeneration, leading to blindness in the first three decades of life. It is associated with mutations in the cadherin 3 gene, resulting in the abnormal expression of P-cadherin. We report a case of a 4-year-old female patient diagnosed with this genodermatosis.info:eu-repo/semantics/publishedVersio

Sparse scalp hair and vision loss: think hypotrichosis with juvenile macular dystrophy

Here, we report the diagnostic challenge of a female patient of Russian descent with autosomal recessive hypotrichosis with juvenile macular dystrophy (HJMD). She presented to dermatology age one and a half years with sparse hair growth on her scalp, her parents were reassured this would grow, but it never manifested. She was found to be hypermetropic and prescribed glasses from age 2 but no retinal findings were noted. At age 23 years, the patient undertook an internet search and discovered the association of symptoms pointing towards HJMD. She sought genetic testing, revealing a homozygous missense mutation in Cadherin-3 (CDH3) gene. The patient presented to our Genetic Eye Disease Service at Moorfields Eye Hospital age 27 years, with reduced colour, central distance and near vision. Fundus examination and imaging confirmed atrophic macular changes. Currently, HJMD has no treatment, she wears a wig, UV-protected sunglasses in sunlight and maintains a healthy balanced diet

A KRT71 Loss-of-Function Variant Results in Inner Root Sheath Dysplasia and Recessive Congenital Hypotrichosis of Hereford Cattle

Genodermatoses, such as heritable skin disorders, mostly represent Mendelian conditions. Congenital hypotrichosis (HY) characterize a condition of being born with less hair than normal. The purpose of this study was to characterize the clinicopathological phenotype of a breed-specific non-syndromic form of HY in Hereford cattle and to identify the causative genetic variant for this recessive disorder. Affected calves showed a very short, fine, wooly, kinky and curly coat over all parts of the body, with a major expression in the ears, the inner part of the limbs, and in the thoracic-abdominal region. Histopathology showed a severely altered morphology of the inner root sheath (IRS) of the hair follicle with abnormal Huxley and Henle’s layers and severely dysplastic hair shafts. A genome-wide association study revealed an association signal on chromosome 5. Homozygosity mapping in a subset of cases refined the HY locus to a 690 kb critical interval encompassing a cluster of type II keratin encoding genes. Protein-coding exons of six positional candidate genes with known hair or hair follicle function were re-sequenced. This revealed a protein-changing variant in the KRT71 gene that encodes a type II keratin specifically expressed in the IRS of the hair follicle (c.281delTGTGCCCA; p.Met94AsnfsX14). Besides obvious phenocopies, a perfect concordance between the presence of this most likely pathogenic loss-of-function variant located in the head domain of KRT71 and the HY phenotype was found. This recessive KRT71-related form of hypotrichosis provides a novel large animal model for similar human conditions. The results have been incorporated in the Online Mendelian Inheritance in Animals (OMIA) database (OMIA 002114-9913)

Is Bimatoprost Effective In Increasing Satisfaction In Patients At Least 12 Years Old With Eyelash Hypotrichosis?

OBJECTIVE: The objective of this systematic review is to determine whether or not bimatoprost 0.03% improves satisfaction in patients at least 12 years old with eyelash hypotrichosis. STUDY DESIGN: Systematic review of three multicenter, double-masked, randomized, parallel group studies, all published in English between 2015 and 2016. DATA SOURCES: All three studies used in this review were researched via PubMed and were published in peer-reviewed journals. OUTCOMES MEASURED: Patient satisfaction was measured using the Eyelash Satisfaction Questionnaire (ESQ) in all three studies. RESULTS: Wirta et al. (J Clin Aesthet Dermatol. 2015;8:11–20.) found a statistically significant relationship between bimatoprost 0.03% and satisfaction with a p=0.004. Borchert et al. (Clin Ophthalmol. 2016;10:419-29. doi:10.2147/OPTH.S89561) did not indicate a p-value but 78.2% of subjects treated with bimatoprost 0.03% and 65% of subjects in the control were found to have an increase in satisfaction of eyelash growth at the end of the study. The study conducted by Glaser et al. (Br J Dermatol. 2015;172(5):1384-94.) did not find a statistically significant relationship between bimatoprost 0.03% and satisfaction with p=0.25. CONCLUSIONS: The results of these studies show that the objective question remains inconclusive in regard to increasing patient satisfaction after the use of bimatoprost 0.03% as only one out of the three studies showed a statistically significant relationship. Further studies should be conducted with researchers not employed by the pharmaceutical company who manufactures the product