Analysis of a Break in Chromosome 14 Mapping to the Region of the Immunoglobulin Heavy Chain Locus

• Published in: Proceedings of the National Academy of Sciences - PNAS 1983-04, Vol.80 (7), p.1997-2001
• Main Authors: Linsley, Peter S., Bech-Hansen, N. Torben, Siminovitch, Louis, Cox, Diane W.
• Format: Article
• Language: English
• Subjects: Chromosome Aberrations; Chromosome Mapping; Chromosomes; Chromosomes, Human, 13-15; DNA; DNA probes; Genes; Genetic hybridization; Genetic inheritance; Genetic loci; Haplotypes; Humans; Immunoglobulin gamma-Chains - genetics; Immunoglobulin Heavy Chains - genetics; Nucleic Acid Hybridization; Polymorphism, Genetic; Restriction fragment length polymorphism; Ring chromosomes
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.80.7.1997

We have detected restriction fragment length polymorphisms associated with the immunoglobulin heavy chain Cγgenes. DNA from both parents of an individual having an unbalanced rearrangement of the long arm of chromosome 14, region q32 [Cox, D. W., Markovic, V. D. & Teshima, I. E. (1982) Nature (London) 297, 428-430], revealed distinctive patterns of BamHI fragments which hybridized with cloned probes from the Cγ 2-Cγ 4gene cluster. The number of hybridizing fragments in both cases (five) equaled the number of known Cγgenes. Pedigree and densitometric analyses indicated that the proband did not have any maternal complement of Cγgene-hybridizing fragments. Included on the deleted chromosomal segment was a Cγgene having properties of the previously reported Cγpseudogene. We also examined DNA from this family with a probe for the highly polymorphic locus D14S1, which recently was demonstrated to be tightly linked to the Cγ 1gene locus [Balazs, I., Purrello, M., Rubinstein, P., Alhadeff, B. & Siniscalco, M. (1982) Proc. Natl. Acad. Sci. USA 79, 7395-7399]. EcoRI and EcoRI-BamHI fragments from both parents hybridized with a probe for this locus in DNA from the proband, indicating that, unlike the Cγgene family, D14S1 was not deleted from the abnormal chromosome. Thus, the chromosomal breakpoint in the proband lies within region 14q32 between the two tightly linked markers, D14S1 and the Cγ 1heavy chain gene locus. The D14S1 locus must lie proximal to the centromere relative to the Cγgene family. The genetic variability detected with Cγgene probes may prove useful for genetic analysis of structural rearrangements involving this region of chromosome 14.