Abstract
P 097
Ocular albinism in a large family
Elena Khurieva, Leonie Troeber, Zisis Gkatzioufas, Ursula Löw, Berthold Seitz, Barbara Käsmann-Kellner
Klinik für Augenheilkunde, Universitätskliniken des Saarlandes, Homburg/Saar
Objective
Albinism is a common cause of congenital visual impairment. There are two different types of albinism: oculocutaneous albinism (OCA) and ocular albinism (OA). Ocular albinism is inherited in a X-linked recessive way and is characterised by a positive family history on the mother´s side with albinism in male patients, while OCA as autosomal-recessive disease affects male and female patients equally, both parents are gene carriers.
Methods
In a retrospective clinical study, we examined a family displaying males with albinism expanding over 2 generations. In the last 15 years we observed the clinical course of the disease over the next 2 generations, which proved to be a difficult task because of the complicated family settings (some of the affected children no longer lived with the parents, others were adopted). Within 32 family members there were 13 male patients with ocular albinism, 7 female carriers of ocular albinism and 2 male suspects of carrying the initial gene mutation in this family.
Results
Our results showed that all fathers in the family tree passed on the gene mutation to their daughters. All male offsprings of these women manifested ocular albinism except for one boy. Female patients carrying the gene responsible for albinism also exhibited functional disabilities: nystagmus and decreased visual acuity.
Conclusions
Despite the well-known literature our study showed a marked “pseudo-dominance” of albinism in male members of this family. In addition, two female carriers presented with clinical signs and functional pathologies. Nevertheless, this family as well presents the classical form of x-chromosomal-recessive ocular albinism, just showing the extremes of statistical distribution with a family presenting with affected boys only, and the expected 50% rate of healthy males missing.
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