期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1974
卷号：71
期号：4
页码：1569-1573
DOI：10.1073/pnas.71.4.1569
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Knowledge of the genetic relationships between {beta}-D-N-acetylhexosaminidases A and B (EC 3.2.1.30 ) may help in understanding the hexosaminidase deficiency associated with GM2 gangliosidosis, a fatal lipid storage disease in man. Through the use of man-mouse somatic cell hybrids we have found that a gene involved in hexosaminidase A expression was linked to the genes coding for mannosephosphate isomerase and pyruvate kinase-3. The gene coding for hexosaminidase B was not linked to any of the genes coding for 25 enzyme markers tested. A combination of immunological and electrophoretic techniques was employed to identify human hexosaminidases A and B with certainty in cell hybrids. Discordant segregation of hexosaminidase A and hexosaminidase B in 60 clones indicated that the genes coding for their expression were not linked. However, hexosaminidase A was never expressed in cell hybrids in the absence of hexosaminidase B. This suggests that the gene responsible for the hexosaminidase A phenotype, linked to mannosephosphate isomerase and pyruvate kinase-3, requires the presence of the gene coding for hexosaminidase B for the expression of hexosaminidase A. These observations offer a genetic explanation for the biochemical and immunological relationships between hexosaminidases A and B and provide the framework for identifying the basic genetic defects responsible for GM2 gangliosidosis.
关键词：GM2 gangliosidosis ; lysosomal enzymes ; anti-hexosaminidase sera ; electrophoresis
