[show abstract][hide abstract] ABSTRACT: Facioscapulohumeral muscular dystrophy (FSHD) has recently been shown to be associated with deletions that are detectable using probe p13E-11 (D4F104S1). Although these deletions reside within large, highly polymorphic restriction fragments (20-300 kb), the "mutant" fragment is usually shorter than 28 kb and can routinely be detected using conventional agarose gel electrophoresis. Yet, the complete visualization of the alleles requires pulsed-field gel electrophoresis (PFGE). Family studies showed that p13E-11 detects two nonallelic loci in this size range, only one of which originates from chromosome 4q35. We have assigned the other p13E-11 locus to chromosome 10qter by linkage analysis in CEPH pedigrees. Knowing the location of both loci improves the diagnostic reliability, as the exact origin of "small" EcoRI fragments can be determined by haplotyping. Since FSHD shows genetic heterogeneity, this 10qter locus became an interesting candidate to be the second FSHD locus. However, analysis of a large chromosome 4-unlinked FSHD family did not provide evidence for linkage on chromosome 10qter.
[show abstract][hide abstract] ABSTRACT: Histidine-rich glycoprotein (HRG) belongs to the cystatin superfamily and appears to be a potential risk factor for thrombosis. An increased prevalence of elevated HRG plasma levels in patients with venous thrombosis and families with thrombophilia has been reported. It is interesting to note that the genes of four different members of the cystatin superfamily are located on the distal section of the long arm of chromosome 3: Stefin A (STF1) on 3q21, Kininogen (KNG) on 3q26-qter, [alpha]-2-HS-glycoprotein (AHSG) on 3q27-q28, and HRG on 3q21-qter. To further investigate the evolutionary relationship between HRG and members of the cystatin superfamily, the authors isolated a cosmid that was used to refine the chromosomal localization of HRG by in situ hybridization. In addition, they used a dinucleotide repeat polymorphism to localize HRG on the linkage map of chromosome 3q. 10 refs., 2 figs.
[show abstract][hide abstract] ABSTRACT: Facioscapulohumeral muscular dystrophy (FSHD) has been mapped to 4q35 and shown to be associated with deletions that are detectable using probe p13E-11 (D4104S1). These deletions reside within highly polymorphic restriction fragments (20-300 kb) which can normally only be resolved completely using pulsed-field gel electrophoresis (PFGE). Family studies showed that p13E-11 detects two non-allelic loci, only one of which originates from 4q35 origin. In 20 CEPH families, 8 individuals were identified showing a `small` EcoRI fragment detectable by conventional Southern blotting. Linkage analysis allowed assignment of these fragments to 10qter (D10S212 and D10S180) in all families tested. Since FSHD shows genetic heterogeneity, this second p13E-11 locus on 10qter became an interesting candidate as a second FSHD family did not provide evidence for linkage on chromosome 10qter.
The American Journal of Human Genetics 01/1994; 55. · 11.20 Impact Factor