The human myelin-basic-protein gene: chromosomal localization and RFLP analysis.

With a human myelin-basic-protein (MBP) cDNA used as a probe, the human MBP gene has been mapped to chromosome region 18q22-q23 by a combination of Southern hybridization to a panel of somatic-cell hybrid DNAs and in situ hybridization to metaphase chromosomes. Restriction-fragment-length polymorphisms (RFLPs) have also been identified with this probe in human DNA, by means of the restriction enzymes BamHI, PvuII, and PstI. In studies of informative families, the alleles of the BamHI and PvuII polymorphisms have been shown to segregate as Mendelian traits.     

The gene for human chromogranin A (CgA) is located on chromosome 14

Chromogranin A (CgA) is a protein that is present in most neuroendocrine tissues and is co-secreted with their resident hormones. We have assigned the CgA gene to human chromosome 14 by hybridization of a CgA cDNA probe cloned from a cDNA library of human medullary thyroid carcinoma cells to spots of individual human chromosomes flow-sorted onto nitrocellulose filters. Southern analysis of human genomic DNA with the same probe revealed only 1-3 restriction bands. These studies indicate that the CgA gene is probably single copy and not a member of a dispersed, multigene family. The CgA gene is not co-localized with the genes of any of the CgA-associated hormones.     

Mucin 4 (MUC4) gene: regional assignment (3q29) and RFLP analysis.

The use of a probe (JER64) containing a mucin 4 (MUC4) cDNA insert of 1.83 kb allowed to assign by in situ hybridization, the MUC4 gene to 3q29. This probe detected RFLPs with all restriction enzymes used (BamHI, HindIII, PstI, EcoRI, and TaqI). Particularly numerous alleles were observed with PstI, EcoRI and TaqI, in a small sample of unrelated DNAs (25 digested with PstI, 8 with EcoRI and 8 with TaqI). The PIC values were 0.69, 0.63 and 0.70 for PstI, EcoRI and TaqI respectively. The polymorphisms observed of variable number of tandem repeat (VNTR) type are in relation with the presence of tandemly repeated nucleotide sequences in MUC4 gene.