skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Microphthalmia with linear skin defects syndrome (MLS): Characterization of the critical region and isolation of candidate genes

Journal Article · · American Journal of Human Genetics
OSTI ID:133388
; ;  [1]
  1. Baylor College of Medicine, Houston, TX (United States); and others

Microphthalmia with linear skin defects syndrome (MLS) is an X-linked male-lethal disorder characterized by abnormalities in the development of the eye, skin, and brain. We defined the MLS critical region through analysis of hybrid cell lines retaining various deletion breakpoints in Xp22, including cell lines from 17 female patients showing features of MLS. Using a combination of YAC cloning and long-range restriction analysis, the MLS candidate region was estimated to be 450-550 kb. A minimally overlapping cosmid contig comprised of 20 cosmid clones was subsequently developed in this region. These cosmids are currently being used to isolate expressed sequences using cross-species conservation studies and exon-trapping. An evolutionarily conserved sequence isolated from a cosmid within the critical region has been used to isolate several overlapping cDNAs from a human embryonic library. Northern analysis using these cDNA clones identified a 5.2 kb transcript in all tissues examined. Sequence analysis revealed a 777 base pair open reading frame encoding a putative 258 amino acid protein. Using the exon-trapping method, fifty-four putative exons have been isolated from fourteen cosmids within the critical region. The expression patterns of the genes containing these exons are being analyzed by polymerase chain reaction (PCR) using reverse-transcribed mRNA from several human tissues and primers corresponding to the exon sequences. Using this approach in combination with exon connection, we determined the four of the trapped exons belong to the same cDNA transcript, which is expressed in adult retina, lymphoblast, skeletal muscle, and fetal brain. To date, we have isolated and sequenced 1 kilobase of this gene, all of which appears to be open reading frame. Both of the genes isolated from the critical region are being analyzed as possible candidates for MLS.

OSTI ID:
133388
Report Number(s):
CONF-941009-; ISSN 0002-9297; TRN: 95:005313-0116
Journal Information:
American Journal of Human Genetics, Vol. 55, Issue Suppl.3; Conference: 44. annual meeting of the American Society of Human Genetics, Montreal (Canada), 18-22 Oct 1994; Other Information: PBD: Sep 1994
Country of Publication:
United States
Language:
English