Distribution and characterization of a sandhoff disease-associated 50-kb deletion in the gene encoding the human β-hexosaminidase β-chain

• Published in: Human genetics Vol. 85; no. 3; pp. 327 - 329
• Main Authors: BIKKER, H, VAN DEN BERG, F. M, WOLTERMAN, R. A, KLEIJER, W. J, DE VIJLDER, J. J. M, BOLHUIS, P. A
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01-08-1990; Berlin; New York, NY
• Subjects: beta-N-Acetylhexosaminidases - genetics; Biological and medical sciences; Chromosome Deletion; Errors of metabolism; Europe; Genetic Testing; Hexosaminidase B; Homozygote; Humans; Lipids (lysosomal enzyme disorders, storage diseases); Medical sciences; Metabolic diseases; Polymorphism, Restriction Fragment Length; Restriction Mapping; Sandhoff Disease - genetics; Europe; Human; Gene; Enzyme; Beta-Peptide chain; Restriction map; Deletion; Lipids; Metabolic diseases; Sandhoff disease; Hexosaminidase; Genetic disease
• ISSN: 0340-6717; 1432-1203
• DOI: 10.1007/BF00206756

A 50-kb deletion was demonstrated in the gene encoding for the beta-subunit of human hexosaminidase (HEXB), using field inversion gel electrophoresis (FIGE) of SfiI-digested chromosomal DNA from patients with Sandhoff disease. We investigated 14 patients from different parts of Europe and found no deletion in 5 patients, 2 patients homozygous for the deletion, and 7 patients with the deletion in one allele. The distribution of the 50-kb deletion was approximately in agreement with the Hardy-Weinberg equilibrium. The deletion was characterized using chromosomal DNA from one of the two homozygous patients. Restriction fragments were hybridized with a 1.6-kb (almost complete) and a 0.4-kb (5') HEXB cDNA clone. It appeared that the deletion started in intron 5, extending in the 5' direction and causing the loss of exon 1-5 and the promoter area of the HEXB gene.