Abstract
Two pairs of alleles, at the two loci of hexosaminidase (HEX), were found to segregate in an Arab inbred family: the normal and the mutant Tay-Sachs (TSD) alleles of HEX A, and the normal and a mutant allele of HEX B. Since the mutant HEX B is heat labile, no reliable identification of TSD genotypes can be obtained in its presence, as long as the proportions of HEX A and B are estimated by the routinely used heat-inactivation method. The genotypes may be correctly identified in such cases by separation of the two isoenzymes on ion-exchange chromatography, estimating their individual activities, and calculating the ratio between them. Of the nine genotype combinations possible with these two pairs of alleles, five have been identified in the reported family by this procedure.
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Selected References
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- Beutler E., Yoshida A., Kuhl W., Lee J. E. The subunits of human hexosaminidase A. Biochem J. 1976 Dec 1;159(3):541–543. doi: 10.1042/bj1590541. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dreyfus J. C., Poenaru L., Vibert M., Ravise N., Boue J. Characterization of a variant of beta-hexosaminidase: "hexosaminidase Paris". Am J Hum Genet. 1977 May;29(3):287–293. [PMC free article] [PubMed] [Google Scholar]
- Geiger B., Arnon R. Chemical characterization and subunit structure of human N-acetylhexosaminidases A and B. Biochemistry. 1976 Aug 10;15(16):3484–3493. doi: 10.1021/bi00661a014. [DOI] [PubMed] [Google Scholar]
- Hechtman P., Rowlands A. Apparent hexosaminidase B deficiency in two healthy members of a pedigree. Am J Hum Genet. 1979 Jul;31(4):428–438. [PMC free article] [PubMed] [Google Scholar]
- Lane A. B., Jenkins T. Two variant hexosaminidase beta-chain alleles segregating in a South African family. Clin Chim Acta. 1978 Jul 15;87(2):219–228. doi: 10.1016/0009-8981(78)90341-8. [DOI] [PubMed] [Google Scholar]
- Lee J. E., Yoshida A. Purification and chemical characterization of human hexosaminidases A and B. Biochem J. 1976 Dec 1;159(3):535–539. doi: 10.1042/bj1590535. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lowden J. A. Evidence for a hybrid hexosaminidase isoenzyme in heterozygotes for Sandhoff disease. Am J Hum Genet. 1979 May;31(3):281–289. [PMC free article] [PubMed] [Google Scholar]
- Momoi T., Sudo M., Tanioka K., Nakao Y. Tay-Sachs disease with altered beta-hexosaminidase B: a new variant? Pediatr Res. 1978 Feb;12(2):77–81. doi: 10.1203/00006450-197802000-00001. [DOI] [PubMed] [Google Scholar]
- Padeh B., Navon R. Diagnosis of Tay-Sachs disease by hexosaminidase activity in leukocytes and amniotic fluid cells. Isr J Med Sci. 1971 Feb;7(2):259–263. [PubMed] [Google Scholar]
- Price R. G., Dance N. The demonstration of multiple heat stable forms of N-acetyl- -glucosaminidase in normal human serum. Biochim Biophys Acta. 1972 Jun 22;271(1):145–153. doi: 10.1016/0005-2795(72)90142-0. [DOI] [PubMed] [Google Scholar]
- Robinson D., Stirling J. L. N-Acetyl-beta-glucosaminidases in human spleen. Biochem J. 1968 Apr;107(3):321–327. doi: 10.1042/bj1070321. [DOI] [PMC free article] [PubMed] [Google Scholar]