X chromosome-specific cDNA arrays: identification of genes that escape from X-inactivation and other applications.
Mutant alleles are frequently characterized by low expression levels. Therefore, cDNA array-based gene expression profiling may be a promising strategy for identifying gene defects underlying monogenic disorders. To study the potential of this approach, we have generated an X chromosome-specific microarray carrying 2423 cloned cDNA fragments, which represent up to 1317 different X-chromosomal genes. As a prelude to testing cell lines from patients with X-linked disorders, this array was used as a hybridization probe to compare gene expression profiles in lymphoblastoid cell lines from normal males, females and individuals with supernumerary X chromosomes. Measurable hybridization signals were obtained for more than half of the genes represented on the chip. A total of 53 genes showed elevated expression levels in cells with multiple X chromosomes and many of these were found to escape X-inactivation. Moreover, the detection of a male-viable deletion encompassing three genes illustrates the utility of this array for the identification of small unbalanced chromosome rearrangements.
Sudbrak
R
R
Max-Planck Institute for Molecular Genetics, Ihnestrasse 73, D-14195, Berlin, Germany.
Wieczorek
G
G
Nuber
U A
UA
Mann
W
W
Kirchner
R
R
Erdogan
F
F
Brown
C J
CJ
Wöhrle
D
D
Sterk
P
P
Kalscheuer
V M
VM
Berger
W
W
Lehrach
H
H
Ropers
H H
HH
D000483:Alleles; D000818:Animals; D002460:Cell Line; D002869:Chromosome Aberrations; D018076:DNA, Complementary / Q000378:metabolism*; D004303:Dosage Compensation, Genetic; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D008297:Male; D009154:Mutation; D009693:Nucleic Acid Hybridization; D020411:Oligonucleotide Array Sequence Analysis; D016133:Polymerase Chain Reaction; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012737:Sex Factors; D014960:X Chromosome
D018076:DNA, Complementary