title: Low incidence of deletion of the esterase D locus in retinoblastoma patients.
abstract: Esterase D was quantitatively measured in the red blood cells from three patients from three separate kindreds who had abnormalities of chromosome 13. The esterase D activity was proportional to the number of copies of the q14 region of chromosome 13 present. These findings confirm published data localizing the esterase D gene to chromosome band 13q14, a region which is important in the etiology of retinoblastoma. Fifty-one additional retinoblastoma patients not known to have any chromosomal defect also underwent esterase D determination. In none of these patients did the esterase D measurement detect a 13q14 deletion. The normal esterase D levels in this series of 51 retinoblastoma patients suggest that deletion of an esterase D locus is infrequent in retinoblastoma patients. It must be noted that patients who are mosaics, with a 13q14 deletion in only a fraction of all somatic cells, could possibly have normal red blood cell esterase D levels. Further study is necessary to determine if esterase D determination of all retinoblastoma patients is a worthwhile clinical tool.
mesh_terms: D000293:Adolescent; D000328:Adult; D043182:Carboxylesterase; D002265:Carboxylic Ester Hydrolases / Q000097:blood / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D002872:Chromosome Deletion; D002901:Chromosomes, Human, 13-15 / Q000648:ultrastructure*; D005134:Eye Neoplasms / Q000201:enzymology / Q000235:genetics*; D005260:Female; D006801:Humans; D007223:Infant; D007527:Isoenzymes / Q000097:blood / Q000235:genetics; D008297:Male; D008875:Middle Aged; D012175:Retinoblastoma / Q000201:enzymology / Q000235:genetics*; D014314:Trisomy
chemical_list: D007527:Isoenzymes; D002265:Carboxylic Ester Hydrolases; D043182:Carboxylesterase; C020118:ESD protein, human