Failure to detect connexin43 mutations in 38 cases of sporadic and familial heterotaxy.
BACKGROUND
Heterotaxy results from failure to establish normal left/right asymmetry during embryonic development. Typical manifestations include complex heart defects and malpositioning of abdominal organs. Missense base substitutions clustered in a 150-base pair region of the gap-junction gene connexin43 (cx43) have been implicated in the pathogenesis of heterotaxy.


RESULTS
cx43 was studied in 38 cases of sporadic and familial heterotaxy. A 400-base pair region containing the previously reported mutation sites was amplified and directly sequenced in 19 patients. Nineteen additional patients were tested for restriction fragments predicted by two of the previously reported missense substitutions. No difference from normal control subjects was detected in any of the patients.


CONCLUSIONS
Randomly selected cases of heterotaxy are unlikely to be the result of mutations in cx43.
Gebbia
M
M
Department of Pathology, Baylor College of Medicine, Houston, Tex 77030, USA.
Towbin
J A
JA
Casey
B
B
D000005:Abdomen / Q000002:abnormalities*; D000015:Abnormalities, Multiple / Q000235:genetics*; D018031:Connexin 43 / Q000235:genetics*; D005260:Female; D006330:Heart Defects, Congenital / Q000235:genetics*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D015183:Restriction Mapping; D013154:Spleen / Q000002:abnormalities*
D018031:Connexin 43