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Updated: Aug 19, 2026

RNA-Seq Analysis of Differential Gene Expression in Electroporated Chick Embryonic Spinal Cord
Published on: November 1, 2014
Localization of human X chromosomal mental retardation (MRX) genes in chicken and comparison with the chicken genome
M Kohn1, H Kehrer-Sawatzki, H Hameister
1Department of Human Genetics, University Ulm, Ulm, Germany.
Abstract:
In an ongoing study human X chromosomal mental retardation genes (MRX) were mapped in the chicken genome. Up to now the homologs of 13 genes were localized by FISH techniques. Four genes from HSAXp (TM4SF2, RSK2/RPS6KA3, NLGN4, ARX) map to GGA1q13-->q31, and seven genes from HSAXq (OPHN1, AGTR2, ARHGEF6, PAK3, FACL4/ACS4, FMR2, ATRX) to GGA4p. The gene-rich region of HSAXq28 proved to be much less conserved. GDI1 localized to GGA1pter and SLC6A8 to a mid-sized microchromosome. The order of the genes was determined from the newly available genome sequence data from chicken, which reveals exact colinearity between the genes in HSAXp and GGA1q13-->q31, but completely scrambled gene order between the genes with common synteny from HSAXq and GGA4p. This result supports the hypothesis that the human X chromosome is a real ancient autosomal linkage group.
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