Figure 6From: The Facioscapulohumeral muscular dystrophy region on 4qter and the homologous locus on 10qter evolved independently under different evolutionary pressure 10q alleles with qB telomere. Allelic pattern of individuals carrying 10q alleles with a qB type telomere. a) The segregation study with the D4S139 probe demonstrates that the two sisters inherited the same 4q alleles of 150 and 60 kb. I:1 shows a trisomic pattern with a BlnI-resistant 10q of 32 kb (*) and a standard 10q of 45 kb. The analysis of the telomeric sequences reveals that the variant 10q allele of 32 kb has a qB telomere. The two 4q alleles and the standard 10q allele of 45 kb have qA telomeres. b) The patient is trisomic and carries a FSHD allele of 33 kb and a standard 10 q allele of 70 kb with a qA telomere. We can not distinguish the 10q variant allele from the 4q standard alleles. Since both the 85 kb and 55 kb show a qB telomere, we deduce that the variant 10q allele carries a qB telomere. c) The 4q short allele of 20 kb segregates with FSHD in the family. The affected daughter (II:1) is trisomic and inherited from the mother (I:1) both the FSHD-linked 4q of 20 kb and the BlnI-resistant 10q allele of 49 kb (*) and from the father a standard 10q allele of 70 kb and a 4q standard allele of 100 kb. The analysis of the telomeric sequences shows that the variant 10q allele of 49 kb has a qB telomere, while the 10q standard allele of 70 kb and both 4q alleles of 100 and 70 kb have a qA telomere. The 10q variant allele of 49 kb is represented in figure 5 (n.11).Back to article page