Mother knows best

This article by Kacker (10 January, p 144) contained misleading genetic information. Lipoid proteinosis is an autosomal, not a sex linked, recessive disorder. The fact that the child’s parents were first cousins suggested the possibility of an autosomal recessive disorder, but would have been irrelevant in the case of a sex-linked one. The involvement of the two brothers, but not of the two sisters, must have been a chance occurrence.