Members of this family of proteins may have a role in the beta-catenin-Tcf/Lef signaling pathway, as well as in the process of myelination of the central and peripheral nervous system. Defects in Hyccin are the cause of hypomyelination with congenital cataracts [MIM:610532]. This disorder is characterised by congenital cataracts, progressive neurologic impairment, and diffuse myelin deficiency. Affected individuals experience progressive pyramidal and cerebellar dysfunction, muscle weakness and wasting prevailing in the lower limbs [1][2].

1: Deficiency of hyccin, a newly identified membrane protein, causes hypomyelination and congenital cataract. Zara F, Biancheri R, Bruno C, Bordo L, Assereto S, Gazzerro E, Sotgia F, Wang XB, Gianotti S, Stringara S, Pedemonte M, Uziel G, Rossi A, Schenone A, Tortori-Donati P, van der Knaap MS, Lisanti MP, Minetti C; Nat Genet. 2006;38:1111-1113. PMID:16951682

2: Isolation and characterization of a novel human gene, DRCTNNB1A, the expression of which is down-regulated by beta-catenin. Kawasoe T, Furukawa Y, Daigo Y, Nishiwaki T, Ishiguro H, Fujita M, Satoh S, Miwa N, Nagasawa Y, Miyoshi Y, Ogawa M, Nakamura Y; Cancer Res. 2000;60:3354-3358. PMID:10910037