Cytogenetic location: 4p16-p15.2 Genomic coordinates (GRCh38): 4:6,000,000-27,700,000Gray-McGuire et al. (2000) presented the result of a genome scan of 126 ...
Cytogenetic location: 4p16-p15.2 Genomic coordinates (GRCh38): 4:6,000,000-27,700,000
Gray-McGuire et al. (2000) presented the result of a genome scan of 126 pedigrees with 2 or more cases of SLE, including 469 sib pairs (affected and unaffected) and 175 affected relative pairs. Using the revised multipoint Haseman-Elston regression technique for concordant and discordant sib pairs and a conditional logistic regression technique for affected relative pairs, they identified linkage to chromosome 4p16-p15.2 (p = 0.0003, lod = 3.84) and presented evidence of an epistatic interaction between 4p16-p15.2 and chromosome 5p15 in European American families. Using data from an independent pedigree collection, they confirmed the linkage to 4p16-p15.2 in European American families. The most significant linkage that they found in the African American subset was to the previously identified region on 1q (SLEB1; 601744).
Nath et al. (2002) found that lod scores were higher when linkage analysis was confined to families in which at least 1 SLE patient was diagnosed with the presence of neuropsychiatric manifestations such as seizures and psychosis. The authors stated that the segregation behavior of this linked locus suggested a dominant mode of inheritance with an almost 100% homogeneous genetic effect in these pedigrees.
Xing et al. (2007) reanalyzed the 77 European American families consisting of 301 full sib pairs previously studied by Gray-McGuire et al. (2000) and confirmed significant linkage at 4p (p = 0.000087). The linkage signal at 4p16 was replicated in another cohort of 76 European American families consisting of 221 full sib pairs (p = 0.0047). Two-point and multipoint model-based linkage analyses in all 153 families yielded maximum lod scores of 3.51 and 4.84 at D4S3007, respectively, under a recessive model with penetrance of 0.8. Haplotype analysis using densely spaced microsatellite markers in the linkage region localized the potential SLE susceptibility locus telomeric to D4S2928. A genomewide linkage scan revealed significant interaction between 4p16 and 2p11 (p = 0.003) and 19q13 (p = 0.0094), with marginal interaction at 12q24 (p = 0.066).