1. ¹Center for Global Health and Diseases, Case Western Reserve University, Wolstein Research Building, Room 4133, 2103 Cornell Road, Cleveland, OH 44106-7286, USA
2. ²Department of Pediatrics, University of Cairo, Egypt
3. ³Department of Nephrology, Division of Genetic Epidemiology, University of Cairo, Egypt
4. ⁴Department of Epidemiology and Biostatistics, Case University, Cleveland, OH, USA

Correspondence: Dr R Blanton, Center for Global Health and Diseases, Case Western Reserve University, Wolstein Research Building, Room 4133, 2103 Cornell Road, Cleveland, OH 44106-7286, USA. Tel: +1 216 368 4818; Fax: +1 216 368 4825; E-mail: reb6@po.cwru.edu

Received 22 July 2004; Revised 30 November 2004; Accepted 19 January 2005; Published online 9 March 2005.

Abstract

A minority of individuals infected with the parasite Schistosoma mansoni develops hepatic fibrosis. HLA studies in Egypt and a candidate gene search in a Sudanese population indicate that the host's genetics contribute to disease susceptibility. In an Egyptian community, 32.7% of individuals 11 years and older had significant fibrosis by WHO ultrasound criteria. Linkage to 10 candidate genes was tested using 89 affected sibling pairs from 40 pedigrees in this community. The candidates included genes that initiate fibrosis, participate in collagen synthesis, or control collagen degradation. Two to four single-nucleotide polymorphisms (SNPs) were genotyped per locus, and 188 individuals were genotyped at 48 markers. Model-free modified Haseman–Elston analysis identified linkage to a SNP in the interferon gamma receptor locus (P=0.000001). There was also weak evidence for linkage to the interleukin 13-4 region and tissue growth factor beta 1.