Carriers of Ocular Albinism With and Without Ocular Changes

Albinism in childhood: a flash VEP and ERG study.

“…'3 Female heterozygotes display a mosaic fundal appearance with small patches of hypopigmentation intermixed with pigmented areas. '5 However, the fundal picture varies, and both obligate heterozygotes without fundus changes9 16 23 The intensity of the nystagmus often lessens with age, and this may be associated with improvement in visual performance.23 All albino mammals appear to have anomalous projection of fibres in both the visual202434 and auditory modalities35" (Fig 1). In the normally pigmented person fibres derived from the nasal half of the retina of each eye decussate at the chiasm, while temporal retinal fibres are uncrossed and project to the ipsilateral hemispere.…”

X-linked ocular albinism (Nettleship-Falls): a novel 29-bp deletion in exon 1.

“…Hypopigmentation of the fundus in albinoidism can be differentiated from ocular albinism by the lack of significant visual impairment and nystagmus. Ophthalmoscopic examination of carriers in Xlinked ocular albinism is a prerequisite for confirmation of the diagnosis because there are diagnostic ocular findings in female carriers [8,16,18]. Charles and coworkers observed that 74% of obligate carriers had iris transillumination defects, against 20% of controls.…”

“…Female carriers show iris retroillumination and patchy or striated hyperpigmentation of the retinal pigment epithelium [13,14]. In most carriers visual acuity is normal, but both reduced visual acuity and nystagmus, similar to an affected male, have been described [16]. From the clinical point of view the most reliable sign of the carrier state may be the "mud-splattered" fundus appearance with hyperpigmented streaks in the periphery of the retina [8].…”

Nystagmus and Related Oscillations

“…Tarpey et al (2006) concluded that mutations of the FRMD7 gene are a major cause of the commoner X-linked form. In the case of X-linked ocular albinism, the mother often shows carrier-state characteristics of the disease (Gillespie and Covelli 1963). In the case of X-linked ocular albinism, the mother often shows carrier-state characteristics of the disease (Gillespie and Covelli 1963).…”