Pigmentation disorders such as albinism are occasionally associated with hearing impairments in mammals. Therefore, we wanted to investigate whether such a phenomenon also exists in non-mammalian vertebrates. We measured the hearing abilities of normally pigmented and albinotic specimens of two catfish species, the European wels Silurus glanis (Siluridae) and the South American bronze catfish C...

Hermansky-Pudlak syndrome (HPS) is an autosomal recessive disorder characterized by oculocutaneous albinism, bleeding tendency, and lysosomal accumulation of ceroid-like material, with occasional development of interstitial pneumonia (IP). Nine genetically distinct subtypes of HPS are known in humans; IP develops primarily in types 1 and 4. Most reported cases of HPS with IP are type 1, and the...

Tyrosinase is encoded by the Tyr (c or albino) locus and is the key enzyme in pigment biosynthesis. Loss of function of this enzyme caused by gene mutation results in albinism. Most cases of albinism are caused by missense mutations of tyrosinase. Albino mutations in Tyr have been identified in various animals, including human, mouse, rat, rabbit, cattle, cat, and ferret, but not in gerbil. We ...

Pigmentation disorders span the genetic spectrum from single-gene autosomal recessive disorders such as oculocutaneous albinism (OCA), the autosomal dominant disorder piebaldism to X-linked ocular albinism and multifactorial vitiligo. OCA connotes a group of disorders that result in hypopigmented skin due to decreased melanin production in melanocytes and loss of visual acuity. There are four n...

PURPOSE To quantify the spatial and temporal nature of congenital periodic alternating nystagmus (PAN) and to test the hypothesis that PAN results from a temporal shift in the null zone. METHODS Twenty-five subjects with oculocutaneous albinism (16 tyrosinase negative and 9 tyrosinase positive) and 7 with ocular albinism (5 x-linked and 2 autosomal recessive) participated in the study. Using ...

The effects of mutation on phenotypic expression are supposed to be mainly deleterious because mutations disrupt the expression of genes that function relatively well under current environmental conditions. Thus, mutations are assumed to give rise to deviant phenotypes that are generally selected against. Radioactive contamination in the Chernobyl region of Ukraine is associated with a signific...

A subject with clinical and biochemical tyrosinase positive oculocutaneous albinism (OCA) also had a balanced translocation, 46,XY,t(2;4)(q31.2;q31.22). This observation provides evidence for a possible gene locus in the q31 region of chromosome 2 or 4.

PURPOSE To compare VEP and fMRI as a means of detecting the abnormal visual projections in albinism in different stimulation conditions. METHODS Cortical response to monocular full-field pattern-onset and hemifield pattern-onset and -reversal stimulation of 18 subjects with a known diagnosis of albinism, 17 control subjects, and 6 control subjects with infantile nystagmus syndrome (INS) was d...