Table 1

Results of chromosome 14 STR typing in the maternal UPD(14) family. Data from markers other than chromosome 14 STRs are not shown

STR Coordinate (cM)1-150 Location Father Mother Proband Informativity
D14S72314q11.1-11.21-22-21-2Paternal allele
D14S2831-151 714q11.1-11.23-31-11-2Mutated allele
D14S2854714q13-231-12-22-2Maternal UPD
D14S2586414q23-24.32-31-11-1Maternal UPD
D14S2776914q23-24.31-23-44-4Maternal UPD
D14S688614q24.3-311-12-22-2Maternal UPD
D14S678614q24.3-311-32-42-4Maternal UPD
D14S26711414q322-31-32-3Paternal allele
  • 1-150 The genetic distances and order of markers correspond to the map published by Gyapay et al.19

  • 1-151 A mutation seemed to have occurred in the marker D14S283; the proband showed a maternal allele but also an allele that was larger than the paternal ones. We therefore confirmed paternity by typing 14 different STR markers on nine chromosomes other than 14, all of which showed allelic patterns consistent with paternal inheritance (data not shown). Assuming a mutational event, a dinucleotide repeat expansion would have affected the paternal allele. Such length variations may be caused by strand slippage during replication and have been described before.20