In other species: dog , domestic cat , horse , sheep , rabbit , American mink

Categories: Integument (skin) phene

Links to possible relevant human trait(s) and/or gene(s) in OMIM: 120150 (gene) , 130000 (trait) , 130010 (trait) , 130020 (trait) , 130050 (trait) , 130060 (trait) , 130070 (trait) , 130080 (trait) , 130090 (trait) , 147900 (trait) , 225310 (trait) , 225320 (trait) , 225400 (trait) , 225410 (trait) , 229200 (trait)

Mendelian trait/disorder: unknown

Considered a defect: yes

Cross-species summary: Also known as cutaneous asthenia (CA) or hyperelastosis cutis (HC). Some animals are born with easily extendible and very fragile skin. Severe lacerations result from the slightest scratch. The basic cause of these severe clinical signs is the presence of abnormal collagen in the skin. There are several genes encoding peptides that form procollagen molecules. There are also several genes encoding enzymes that remove excess amino acids from each end of the procollagen molecules, creating mature collagen. Mutations in any of these genes can give rise to Ehlers-Danlos syndrome (see gene-specific entries in OMIA). In general, mutations in collagen structural genes result in dominant forms of the disorder, because heterozygotes produce 50 per cent abnormal collagen molecules. In contrast, mutations in the genes for the enzymes that "process" procollagen generally result in recessive forms of the disorder, because the 50 per cent of normal enzyme activity that occurs in heterozygotes is sufficient to "process" all procollagen molecules. In humans, a detailed classification of the different types of Ehlers-Danlos syndrome has been made, corresponding to mutations in the different genes involved. In animals, most occurrences of the disorder have to be lumped together because the detailed studies necessary for classification have not yet been conducted.