Arylsulfatase D (ARSD)

In the course of positional cloning of the gene mutant in X-linked chondrodysplasia punctata, Franco et al. (1995) identified a cluster of 3 sulfatase genes located in the region Xp22.3. The genes were arylsulfatases and were designated ARSD, ARSE, and ARSF, in that order, proceeding from the telomere of Xp toward the centromere.

ARSD and ARSE have several typical features of genes that map in the pseudoautosomal region of the X chromosome, i.e., they escape X inactivation, have homologs on the Y chromosome, and are not conserved in mouse. ARSD, ARSE, and STS have a conserved gene structure; alignment of the genomic structures revealed perfect conservation of the intron-exon junctions. Sequence analysis of the Y-linked homologs of ARSD and ARSE indicated that they represent truncated pseudogenes.