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).
Rossi et al. BMC Medical Genetics 2007 8:8 doi:10.1186/1471-2350-8-8