Genetic mapping of the gene for androgen-binding protein/sex hormone-binding globulin to mouse chromosome 11

Southern blot analysis of DNAs from Chinese hamster x mouse and rat x mouse somatic cell hybrids showed that the mouse gene encoding androgen-binding protein/sex hormone-binding globulin (ABP-SHBG) is on Chromosome 11. Progeny from an intersubspecies backcross were analyzed to position this locus, termed Shbg, between Il-3 and Int-4 in the middle of this chromosome. Shbg is thus closely linked to several neurological mutations, one of which, Tr, is also associated with male sterility. The recent finding that ABP-SHBG is found throughout the rat brain raises the possibility that one of these mutations may be due to a defect in Shbg.     

Genetic mapping of a new homeobox gene to mouse chromosome 7

A newly identified homeobox gene designated Dbx has been mapped to mouse Chromosome (Chr) 7. This gene is expressed in a restricted manner in developing mouse brain and spinal cord and has amino acid sequence similarities with members of the homeobox gene family such as Drosophila H2.0 and mouse Hlx. Using a fragment of the Dbx cDNA as a probe, a PstI restriction fragment length polymorphism was used to determine genotypes of 144 progeny from an interspecific backcross. Segregation analysis revealed linkage of Dbx with six prepositioned reference loci on mouse Chr 7. No recombination was observed between Dbx and Odc-rs6, indicating that Dbx lies approximately 25 cM distal to the Chr 7 centromere in a region that has conserved linkage relationships with regions of human Chrs 11 and 19.     

Genetic mapping of the rat Lcn2 gene to chromosome 3

The expression of rat 24p3, encoded by the Lcn2 gene, has been associated with rat mammary carcinomas initiated by the neu oncogene (Stoesz and Gould, 1995). In this study, we assign the Lcn2 gene to rat chromosome band 3q12 by genetic linkage analysis.     

Genetic mapping of the mouse ferritin light chain gene and 11 pseudogenes on 11 mouse chromosomes

We typed the progeny of two sets of genetic crosses to determine the map locations for loci containing sequences related to the ferritin light chain (Ft11) gene. Twelve loci were positioned on 11 different chromosomes. One of these genes mapped to a position on Chr 7 predicted to contain the expressed gene on the basis of the previously determined position of the human homolog on 19q13.3-q13.4. Received: 23 July 1997 / Accepted: 20 September 1997     

Genetic mapping of the mouse c-fms proto-oncogene to chromosome 18.

Chinese hamster X mouse somatic cell hybrids were analyzed by Southern blot hybridization with a probe specific for the cellular c-fms proto-oncogene. Results demonstrate that Fms, the genetic locus containing this sequence, maps to mouse chromosome 18. Mouse Fms is thus not linked to the same set of genes involved in growth regulation that human FMS is linked to.     

Molecular cloning of mouse beta 2-glycoprotein I and mapping of the gene to chromosome 11.

beta 2-Glycoprotein I (beta 2 GPI), a plasma protein that binds to anionic phospholipids, is composed of five repeating units called a short consensus repeat (SCR), which is found mostly in the regulatory proteins of the complement system. Recently the human beta 2 GPI gene has been assigned to chromosome 17, not to chromosome 1 where most of the genes of the SCR-containing proteins are clustered. In this report, we have isolated a full-length cDNA clone of mouse beta 2 GPI and determined the chromosomal localization of the gene. The amino acid sequence deduced from the nucleotide sequence of mouse beta 2 GPI revealed 76.1% identity with that of human beta 2 GPI. A genetic mapping by in situ hybridization and linkage analysis using 50 backcross mice has shown that the mouse beta 2 GPI gene (designated B2gp1) is located on the terminal portion of the D region of chromosome 11, closely linked to Gfap, and is 18 cM distal to Acrb, extending a conserved linkage group between mouse chromosome 11 and human chromosome 17. On the basis of these results, the evolutionary relationships among the SCR-containing proteins are discussed.     

Genetic mapping of the polycystic kidney gene,pcy, on mouse chromosome 9

The murine polycystic kidney disease gene,pcy, is an autosomal recessive trait located on chromosome 9. To determine the genetic locus ofpcy, 222 intraspecific backcross mice were obtained by mating C57BL/6FG-pcy andMus molossinus. Restriction fragment length polymorphism analysis of 70 of the 222 backcross progeny showed thatpcy, dilute coat color (d), and cholecystokinin (Cck) were located in the orderd—pcy—Cck from the centromere. Simple sequence repeat length polymorphism analysis of DNA of all 222 backcross mice was carried out using four markers which were located near the central regions ofd andCck. One and eight recombinations were detected betweenD9Mit24 andpcy and betweenD9Mit16 andpcy, respectively. However, no recombinant was observed amongpcy, D9Mit14, andD9Mit148. These findings strongly suggest thatD9Mit14 andD9Mit148 are located near thepcy gene and are good markers for chromosomal walking to this gene.     

Genetic mapping of the integrin alpha 1 gene (Vla1) to mouse chromosome 13.

The integrin alpha 1 chain (Vla1) associates with the beta 1 chain to form a heterodimer that functions as a dual laminin/collagen receptor in neural cells and hematopoietic cells. We have used an interspecies backcross gene-mapping technique to map the Vla1 gene to the distal end of chromosome 13 in the mouse genome. The Vla1 locus is located 3.5 cM distal to Ctla-3 and 7.8 cM distal to Htrla. We have further characterized this locus in recombinant inbred (RI) mice by examining the strain distribution patterns of nine genomic DNA restriction fragment length variants detected with alpha 1 cDNA probes. The RI gene mapping did not show linkage to previously mapped genes or mutants in the AXB, BXA, or AKXD RI sets and therefore defines a new genetic marker for the distal end of chromosome 13 in these RI sets.     

Genetic mapping of the gene for a novel tyrosine kinase, Blk, to mouse chromosome 14

The gene Blk, which encodes a novel tyrosine kinase expressed preferentially in B-lymphoid cells, was mapped by Southern blot analysis of DNA from the progeny of an intersubspecific backcross. Blk maps to the proximal region of chromosome 14 with the gene order centromere--(Np-1,Tcra)-Blk-sys-Es-10.     

Genetic mapping of thet-complex region on mouse chromosome 17 including theHybrid sterility-1 gene

t-haplotypes occupy a region on chromosome (Chr) 17 which slightly overlaps the ends of theT-H-2 interval. The wild-type form of this 14 centi-Morgan (cM) region was mapped in a multilocus backcross (C57BL/10-T×C3H)F₁×C57BL/10 using 15 DNA probes on Southern blots of the DNA extracted from 53 animals which were recombinants in theT-H-2 interval. Each recombinant was also progenytested to ascertain itsHybrid sterility-1 (Hst-1) genotype by crossing to PWB/Ph, aMus musculus-derived inbred strain. The limit of resolution of the cross was 0.27 cM. The map distances have been determined for the DNA loci in theT-H-2 interval and theHst-1 gene was mapped in close vicinity to theD17Rp17 locus.     

Genetic mapping of the gene for a novel tyrosine kinase, Blk, to mouse chromosome 14

The gene Blk, which encodes a novel tyrosine kinase expressed preferentially in B-lymphoid cells, was mapped by Southern blot analysis of DNA from the progeny of an intersubspecific backcross. Blk maps to the proximal region of chromosome 14 with the gene order centromere-(Np-1, Tcra)-Blk-sys-Es-10.