RESUMEN
Ocular albinism of the Nettleship-Falls type (OA1) and X-linked ichthyosis (XI) due to steroid sulfatase (STS) deficiency are cosegregating in three cytogenetically normal half-brothers. The mother has patchy fundal hypopigmentation consistent with random X inactivation in an OA1 carrier. Additional phenotypic abnormalities that have been observed in other STS "deletion syndromes" are not present in this family. STS is entirely deleted on Southern blot in the affected males, but the loci MIC2X, DXS31, DXS143, DXS85, DXS43, DXS9, and DXS41 are not deleted. At least part of DXS278 is retained. Flow cytometric analysis of cultured lymphoblasts from one of the XI/OA1 males and his mother detected a deletion of about 3.5 million bp or about 2% of the X chromosome. Southern blot and RFLP analysis in the XI/OA1 family support the order tel-[STS-OA1-DXS278]-DXS9-DXS41-cen. An unrelated patient with the karyotype 46,X,t(X;Y) (p22;q11) retains the DXS143 locus on the derivative X chromosome but loses DXS278, suggesting that DXS278 is the more distal locus and is close to an XI/OA1 deletion boundary. If a contiguous gene deletion is responsible for the observed XI/OA1 phenotype, it localizes OA1 to the Xp22.3 region.
Asunto(s)
Oftalmopatías/genética , Ictiosis/genética , Epitelio Pigmentado Ocular , Cromosoma X , Arilsulfatasas/genética , Deleción Cromosómica , Mapeo Cromosómico , Sondas de ADN , Citometría de Flujo , Humanos , Linaje , Polimorfismo de Longitud del Fragmento de Restricción , Esteril-SulfatasaRESUMEN
An objective and reproducible method was devised for estimating the malignant potential of ciliochoroidal melanomas after enucleation. This method requires only a single, routine microslide from which nucleolar area and largest tumor dimension are measured. Previous studies have shown these measurements to be reproducible and highly correlated with mortality. To demonstrate a practical method for clinical application of these measurements, a Cox statistical model was derived from 200 cases supplied by the Armed Forces Institute of Pathology. The resulting model, when applied to 340 cases with known outcome from two independent laboratories, allowed subdivision of patients into groups that suffered a six-fold difference in mortality. These results suggest that a central registry, by applying this method to histologic slides from around the world, could provide information useful for the clinical management of patients enucleated for ciliochoroidal melanoma.