BACKGROUND: Neural tube defects (NTDs) are considered complex, with both genetic and environmental factors implicated. To date, no major causative genes have been identified in humans despite several investigations. The first genomewide screen in NTDs demonstrated evidence of linkage to chromosomes 7 and 10. This screen included 44 multiplex families and consisted of 402 microsatellite markers spaced approximately 10 cM apart. Further investigation of the genomic screen data identified a single large multiplex family, pedigree 8776, as primarily driving the linkage results on chromosome 7. METHODS: To investigate this family more thoroughly, a high-density single nucleotide polymorphism (SNP) screen was performed. Two-point and multipoint linkage analyses were performed using both parametric and nonparametric methods. RESULTS: For both the microsatellite and SNP markers, linkage analysis suggested the involvement of a locus or loci proximal to the telomeric regions of chromosomes 2q and 7p, with both regions generating a LOD* score of 3.0 using a nonparametric identity by descent relative sharing method. CONCLUSIONS: The regions with the strongest evidence for linkage map proximal to the telomeres on these two chromosomes. In addition to mutations and/or variants in a major gene, these loci may harbor a microdeletion and/or translocation; potentially, polygenic factors may also be involved. This single family may be promising for narrowing the search for NTD susceptibility genes. (c) 2006 Wiley-Liss, Inc.
BACKGROUND:Neural tube defects (NTDs) are considered complex, with both genetic and environmental factors implicated. To date, no major causative genes have been identified in humans despite several investigations. The first genomewide screen in NTDs demonstrated evidence of linkage to chromosomes 7 and 10. This screen included 44 multiplex families and consisted of 402 microsatellite markers spaced approximately 10 cM apart. Further investigation of the genomic screen data identified a single large multiplex family, pedigree 8776, as primarily driving the linkage results on chromosome 7. METHODS: To investigate this family more thoroughly, a high-density single nucleotide polymorphism (SNP) screen was performed. Two-point and multipoint linkage analyses were performed using both parametric and nonparametric methods. RESULTS: For both the microsatellite and SNP markers, linkage analysis suggested the involvement of a locus or loci proximal to the telomeric regions of chromosomes 2q and 7p, with both regions generating a LOD* score of 3.0 using a nonparametric identity by descent relative sharing method. CONCLUSIONS: The regions with the strongest evidence for linkage map proximal to the telomeres on these two chromosomes. In addition to mutations and/or variants in a major gene, these loci may harbor a microdeletion and/or translocation; potentially, polygenic factors may also be involved. This single family may be promising for narrowing the search for NTD susceptibility genes. (c) 2006 Wiley-Liss, Inc.
Authors: S H Blanton; C Y Liang; M W Cai; A Pandya; L L Du; B Landa; S Mummalanni; K S Li; Z Y Chen; X N Qin; Y F Liu; T Balkany; W E Nance; X Z Liu Journal: J Med Genet Date: 2002-08 Impact factor: 6.318
Authors: T Bjerkedal; A Czeizel; J Goujard; B Kallen; P Mastroiacova; N Nevin; G Oakley; E Robert Journal: Lancet Date: 1982-11-13 Impact factor: 79.321
Authors: Sally John; Neil Shephard; Guoying Liu; Eleftheria Zeggini; Manqiu Cao; Wenwei Chen; Nisha Vasavda; Tracy Mills; Anne Barton; Anne Hinks; Steve Eyre; Keith W Jones; William Ollier; Alan Silman; Neil Gibson; Jane Worthington; Giulia C Kennedy Journal: Am J Hum Genet Date: 2004-05-20 Impact factor: 11.025