AIM: To present a novel strategy for mapping quantitative trait loci (QTL), using human metapopulations. The strategy is based on the expectation that in geographic clusters of small and distinct human isolates, a combination of founder effect and genetic drift can dramatically increase population frequency of rare QTL variants with large effect. In such cases, the distribution of QT measurements in an (affected) isolate is expected to deviate from that observed in neighboring isolates. METHODS: We tested this hypothesis in 9 villages from a larger Croatian isolate resource, where 7 Mendelian disorders have been previously reported. The values of 10 physiological and biochemical QTs were measured in a random sample of 1001 individuals (100 inhabitants of each of 9 villages and 101 immigrant controls). RESULTS: Significant over- or under- representation of individuals from specific villages in extreme ends of standardized QT measurement distribution was found 10 times more frequently than expected by chance. The large majority of such clusters of individuals with extreme QT values (34/36, 94.4%) originated from the 6 villages with the most pronounced geographic isolation and endogamy. CONCLUSION: Early epidemiological assessment supports the feasibility of the proposed strategy. Clusters of individuals with extreme QT values responsible for over-representation of single villages can usually be linked to a larger pedigree and may be useful for further QTL mapping, using linkage analysis.
AIM: To present a novel strategy for mapping quantitative trait loci (QTL), using human metapopulations. The strategy is based on the expectation that in geographic clusters of small and distinct human isolates, a combination of founder effect and genetic drift can dramatically increase population frequency of rare QTL variants with large effect. In such cases, the distribution of QT measurements in an (affected) isolate is expected to deviate from that observed in neighboring isolates. METHODS: We tested this hypothesis in 9 villages from a larger Croatian isolate resource, where 7 Mendelian disorders have been previously reported. The values of 10 physiological and biochemical QTs were measured in a random sample of 1001 individuals (100 inhabitants of each of 9 villages and 101 immigrant controls). RESULTS: Significant over- or under- representation of individuals from specific villages in extreme ends of standardized QT measurement distribution was found 10 times more frequently than expected by chance. The large majority of such clusters of individuals with extreme QT values (34/36, 94.4%) originated from the 6 villages with the most pronounced geographic isolation and endogamy. CONCLUSION: Early epidemiological assessment supports the feasibility of the proposed strategy. Clusters of individuals with extreme QT values responsible for over-representation of single villages can usually be linked to a larger pedigree and may be useful for further QTL mapping, using linkage analysis.
Authors: M G Miano; S G Jacobson; A Carothers; I Hanson; P Teague; J Lovell; A V Cideciyan; N Haider; E M Stone; V C Sheffield; A F Wright Journal: Am J Hum Genet Date: 2000-09-27 Impact factor: 11.025
Authors: Ada Hamosh; Alan F Scott; Joanna Amberger; Carol Bocchini; David Valle; Victor A McKusick Journal: Nucleic Acids Res Date: 2002-01-01 Impact factor: 16.971
Authors: H V Tolk; L Barac; M Pericic; I M Klaric; B Janicijevic; H Campbell; I Rudan; T Kivisild; R Villems; P Rudan Journal: Eur J Hum Genet Date: 2001-09 Impact factor: 4.246
Authors: Veronique Vitart; Zrinka Biloglav; Caroline Hayward; Branka Janicijevic; Nina Smolej-Narancic; Lovorka Barac; Marijana Pericic; Irena Martinovic Klaric; Tatjana Skaric-Juric; Maja Barbalic; Ozren Polasek; Ivana Kolcic; Andrew Carothers; Pavao Rudan; Nick Hastie; Alan Wright; Harry Campbell; Igor Rudan Journal: Eur J Hum Genet Date: 2006-04 Impact factor: 4.246