Deletion of chromosome region 13q14 is transmissible and does not always predispose to retinoblastoma.
During routine screening of retinoblastoma patients for esterase D activity in red blood cell lysates a patient was identified with only 50% of normal enzyme activity. Chromosome analysis showed that this patient had a small deletion within chromosome region 13q14. Parental studies showed that, whereas the father had normal enzyme levels, the mother had esterase D levels which were also 50% of normal and a similar small 13q14 deletion. Ophthalmological examination failed to demonstrate any retinal abnormality in either parent. Thus we present the first case not only of the direct transmission of a 13q14 deletion within a family but also of an individual in whom the deletion has not predisposed to tumour formation.
D002460:Cell Line; D002872:Chromosome Deletion; D002882:Chromosomes, Human, Pair 13; D005134:Eye Neoplasms / Q000235:genetics*; D005260:Female; D005796:Genes; D006801:Humans; D008297:Male; D010375:Pedigree; D010651:Phenylalanine Hydroxylase / Q000235:genetics; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D012175:Retinoblastoma / Q000235:genetics*
D010651:Phenylalanine Hydroxylase