Molecular and cytogenetic analysis in two patients with microdeletions of 7p and Greig syndrome: hemizygosity for PGAM2 and TCRG genes.
Greig cephalopolysyndactyly syndrome (GCPS) is an autosomal dominant disorder that has been mapped to 7p13. We have investigated two patients with GCPS and a cytogenetically visible microdeletion of the short arm of chromosome 7 with gene probes that have been assigned close to the proposed Greig locus. Deletion breakpoints were determined from high-resolution G- and R-banded chromosomes. In patient BC with a de novo deletion (7p12.3-7p14.2) we have found a loss of the genomic region containing the T-cell receptor gamma (TCRG) gene cluster, whereas the other patient IR with a deletion (7p11.2-7p13) due to a de novo translocation was apparently normal for this region. Gene dosage analysis revealed a loss of the phosphoglycerate mutase muscular form (PGAM2) gene locus in both patients. Hox 1.4 and interferon-beta 2 (IFNB2) showed a normal gene dosage. Our investigations revealed the following ordering and assignments of the studied genes: PGAM2 and GCPS in 7p12.3-13; TCRG in the distal part of 7p13-7p14.2; Hox 1.4 and IFNB2 distal to 7p14.2. Our results suggest a location of the TCRG gene more proximal than that reported previously. Furthermore, we were able to exclude the Hox 1.4 gene from involvement in the pathogenesis of GCPS.
Wagner
K
K
Institute of Medical Biology and Human Genetics, University of Graz, Austria.
Kroisel
P M
PM
Rosenkranz
W
W
D001731:Bisphosphoglycerate Mutase / Q000235:genetics*; D002872:Chromosome Deletion; D002874:Chromosome Mapping; D002890:Chromosomes, Human, Pair 20 / Q000648:ultrastructure; D002897:Chromosomes, Human, Pair 7 / Q000648:ultrastructure*; D005147:Facial Bones / Q000002:abnormalities*; D005796:Genes; D005799:Genes, Dominant; D005801:Genes, Homeobox; D005819:Genetic Markers; D006801:Humans; D007370:Interferon Type I / Q000235:genetics; D007527:Isoenzymes / Q000235:genetics; D017880:Limb Deformities, Congenital; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D016692:Receptors, Antigen, T-Cell, gamma-delta; D012886:Skull / Q000002:abnormalities*; D013577:Syndrome; D014178:Translocation, Genetic
D005819:Genetic Markers; D007370:Interferon Type I; D007527:Isoenzymes; D011948:Receptors, Antigen, T-Cell; D016692:Receptors, Antigen, T-Cell, gamma-delta; D001731:Bisphosphoglycerate Mutase