The p.G146A and p.P125P polymorphisms in the steroidogenic factor-1 (SF-1) gene do not affect the risk for hypospadias in Caucasians.

Hypospadias is a frequent congenital malformation in boys and is characterized by incomplete fusion of the urethral folds. The steroidogenic factor-1 (SF-1, NR5A1) gene plays a key role in hypothalamic-pituitary-steroidogenic organ development, and has previously been reported to be mutated in individuals with 46,XY disorder of sex development. Here, we investigated the role of SF-1 in hypospadias, a milder form of 46,XY disorder of sex development. We performed direct sequencing analysis of the SF-1 gene in 2 male Caucasian twins exhibiting very severe hypospadias, and in 95 Caucasian boys with mild and severe hypospadias. We further extended the analysis by investigating 332 mild and severe hypospadias cases and 422 male controls using TaqMan assays. Our sequencing revealed a novel heterozygous p.R313H (c.938G>A) missense mutation in each twin, and no mutations in the 95 Caucasian cases. Instead, a missense p.G146A (c.437G>C), and a silent known p.P125P (c.375C>T) polymorphism, respectively, was found in several of the latter cases. Further investigation of the 2 polymorphisms in the larger material of cases and controls showed no significant genotypic or allelic association. In conclusion, the SF-1 gene may not play a significant role in the development of hypospadias in Caucasians.

Genome-wide identification of quantitative trait loci in a cross between Hampshire and Landrace I: carcass traits.

We report the identification of quantitative trait loci (QTL) affecting carcass composition, carcass length, fat deposition and lean meat content using a genome scan across 462 animals from a combined intercross and backcross between Hampshire and Landrace pigs. Data were analysed using multiple linear regression fitting additive and dominance effects. This model was compared with a model including a parent-of-origin effect to spot evidence of imprinting. Several precisely defined muscle phenotypes were measured in order to dissect body composition in more detail. Three significant QTL were detected in the study at the 1% genome-wide level, and twelve significant QTL were detected at the 5% genome-wide level. These QTL comprise loci affecting fat deposition and lean meat content on SSC1, 4, 9, 10, 13 and 16, a locus on SSC2 affecting the ratio between weight of meat and bone in back and weight of meat and bone in ham and two loci affecting carcass length on SSC12 and 17. The well-defined phenotypes in this study enabled us to detect QTL for sizes of individual muscles and to obtain information of relevance for the description of the complexity underlying other carcass traits.