Mutation analysis of TBX22 reveals new mutation in Tunisian CPX family.
Cleft palate with ankyloglossia (CPX; OMIM 303400) is inherited as a Mendelian semidominant X-Linked disorder. Linkage studies resulted in mapping CPX to Xq13-q 21-31 region. TBX22 was identified as causing CPX. We report a new mutation in a Tunisian family and the first Arab family with X-Linked cleft palate and ankyloglossia. The family includes 6 affected members, 4 males and 2 females. Linkage study was performed using 9 microsatellite markers surrounding the CPX locus with a maximum lod score 1.81 at theta=0 with several markers. Sequence analysis of TBX22 gene revealed a novel change c.358C>T in exon 3 (R120W) located in the T-BOX domain; this change was present in all affected members and none of the 100 controls. A second modification in exon 4 (c.559G>A) predicted to result in a nonconservative substitution (E187 K) was present in the affected members but also in 2 controls, suggesting a polymorphism which functional role cannot be excluded without further study.
Chaabouni
Myriam
M
Laboratoire de génétique humaine faculté de médecine de Tunis et service maladies héréditaires hôpital Charles Nicolle, Tunis Service ORL, hôpital La Rabta, Tunis.
Smaoui
Nizar
N
Benneji
Neila
N
M'rad
Ridha
R
Jemaa
Lamia Ben
LB
Hachicha
Slah
S
Chaabouni
Habiba
H
D002972:Cleft Palate / Q000235:genetics*; D005190:Family; D005260:Female; D006801:Humans; D008297:Male; D009154:Mutation; D010375:Pedigree; D020825:T-Box Domain Proteins / Q000235:genetics*; D014416:Tunisia
D020825:T-Box Domain Proteins; C416943:TBX22 protein, human