Choroideremia: linkage analysis with physically mapped close DNA-markers

✍ Scribed by Eeva-Marja Sankila; Pertti Sistonen; Frans Cremers; Albert Chapelle

• Book ID: 104660832
• Publisher: Springer
• Year: 1991
• Tongue: English
• Weight: 496 KB
• Volume: 87
• Category: Article
• ISSN: 0340-6717
• DOI: 10.1007/bf00200918

✦ Synopsis

We report linkage studies in 18 choroideremia (TCD) families using four closely linked polymorphic markers. Probe pZll, which is known to be deleted in several unrelated patients with TCD, showed no recombinations (Zmax 15.63 at 0 = 0.00). In contrast, one recombination was observed with DXS367, which is also physically very close to TCD. Loci DXS95 and DXYS69 each showed more than one recombination with TCD. Moreover, these analyses revealed a double crossover between TCD and DXYS1, changing the previously reported very close linkage to a recombination fraction of 0.04 with a lod score of 9.93. Multipoint linkage analysis placed TCD proximal to DXS95-DXYS69 and very close to DXS367-pZll with almost identical multipoint lod score maxima either proximal to DXS367 (Zmax = 23.43) or proximal to pZll (Zm~x = 23.36). These results provide a refined linkage map around TCD and will also be useful in DNA diagnostics of the disease.