title: Human DNA sequences isolated with an immunoglobulin switch region probe: sequence, chromosomal localization, and restriction fragment length polymorphisms.
abstract: We have screened a human genomic DNA library with an immunoglobulin (Ig) derived switch (S) region specific probe for homologous sequences. Five Ig independent phage clones were isolated and characterized. The S sequence homologous DNA fragments are short compared to the S region sequences. Ig independent S sequences are flanked by highly repetitive DNA elements and perfect inverted repeats can be demonstrated in their close vicinity. Using subclones of S homologous sequences restriction fragment length polymorphisms were shown within DNA of different T cell leukemias, Burkitt lymphomas, lymphoblastoid cell lines, and DNA of healthy individuals. One of the five clones isolated with the S region probe was evidently localized to chromosome 2 and/or 10 and showed a complex hybridisation pattern with several different human DNAs. S homologous sequences of another clone are most likely localized on chromosome 1. It is possible that these Ig independent S sequences have arisen by amplification and transposition and that they are involved in genetic recombination.
mesh_terms: D001483:Base Sequence; D002874:Chromosome Mapping; D004247:DNA / Q000235:genetics; D004262:DNA Restriction Enzymes; D006801:Humans; D007127:Immunoglobulin Constant Regions / Q000235:genetics; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D007135:Immunoglobulin Variable Region / Q000235:genetics; D011110:Polymorphism, Genetic
chemical_list: D007127:Immunoglobulin Constant Regions; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region; D004247:DNA; D004262:DNA Restriction Enzymes