THE 239AB GENE ON CHROMOSOME-22 - A NOVEL MEMBER OF AN ANCIENT GENE FAMILY

A novel family of genes expressed in human brain has recently been ide ntified. Gene 239FB, transcribed extensively in fetal brain, was isola ted from the chromosome 11p13 region associated with mental retardatio n component of the WAGR (Wilms tumor, aniridia, genitourinary anomalie s, mental retardation) syndrome. This report presents a cDNA sequence and expression profile of a related gene, 239AB, isolated from adult b rain library, that was mapped to chromosome 22. While similar in struc ture, the two genes differ in their expression pattern and may have di fferent roles in central nervous system development and function. In c ontrast to the 239FB, which is expressed predominantly in fetal brain, the 239AB gene is transcribed in adult tissues. Both human genes enco de novel proteins of unknown function that are highly conserved from C aenorhabditis elegans to birds and mammals. Phylogenetic analysis sugg ested that the two lineages of the ancient gene family represented by 239FB and 239AB have been in existence prior to the emergence of moder n animals. (C) 1997 Elsevier Science B.V.