Restriction digests of the clone give the following sizes (kb): HindIII/EcoRI--2.8, 2.0, 0.96, + smaller bands; HindIII--2.8, 2.0, 0.96; EcoRI--6.0, 0.22. Codominant segregation demonstrated in 58 3-generation families for the MspI polymorphism. pMCT112 shows linkage to the Friedreich ataxia locus at a combined total LOD score of 25.09 at a recombination fraction of theta = 0. A single copy fragment of this clone detects the same 450 kb NotI fragment detected by D9S5. Detects genomic restriction fragments of the following sizes (complete digest, kb): NotI--450; EagI--100; BssHII--100; SacII--100. A 1.9 kb SphI fragment of this clone has been used which is devoid of repetitive sequences. The AccI RFLP is observed under normal wash and hybridization stringencies. Pre-association with excess human DNA is required. Enzyme(s) not detecting polymorphism: BglII, PstI, PvuII, RsaI, TaqI. Enzyme(s) not detecting polymorphism: BamHI, BclI, DraI, EcoRI, HincII, HindIII, HinfI, HpaI, KpnI, SalI, SstI, StuI, XbaI. |