This syndrome was first described by John Zachariah Laurence. This is an autosomal recessive disorder associated with loci in chromosomes 11q13, 11q21, 15q22 and 3p13.(54> The syndrome is associated with mental retardation, short stature, spastic paraparesis, hypogenitalism, and red cone dystrophy leading to night blindness by mean age of 9 years and often being registered blind by mean age of 15 years. The prevalence varies between 1 in 125 000 and 1 in 160 000. The prevalence has been reported to be higher in Bedouins of Kuwait (1 in 13 500) and in Newfoundland (1 in 17 500), where a founder effect of a handful of families from the West Country of England in 1800s is thought to be responsible. (55> Laurence-Moon syndrome is usually considered together with Bardet-Biedl syndrome, although strictly this is a separate syndrome. Bardet-Biedl syndrome presents with mental retardation, hypogenitalism, and red cone dystrophy; however, it differs in that central obesity and postaxial polydactyly are characteristic features of this syndrome. This latter syndrome forms the majority of published cases. Associated mental retardation is usually mild to moderate and the majority of males are infertile. About two-thirds suffer from nephrogenic diabetes insipidus, between 15 and 30 per cent develop non-insulin-dependent diabetes mellitus, 30 per cent develop minor renal disease, and 5 per cent go on to develop endstage renal failure.
Was this article helpful?