Pedigrees of Belgian FTLD families DR2 (A) and DR8 (B) showing chromosome 17q21 haplotypes of selected family members based on 18 informative STR markers; allele lengths are indicated in base pairs. The disease haplotype is boxed in black. Inferred haplotypes are shown between parentheses. For deceased patients, genotype data of at-risk offspring was used to deduce their haplotypes. For confidentiality reasons haplotypes are shown only for patients and obligate carriers; the number of at-risk individuals included in the genotyping is indicated within diamonds. In family DR8, the risk haplotype was arbitrarily set for I-1. An arrowhead indicates the index patient.