Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare but 
severe cutaneous adverse drug reactions, which can be caused by a certain number 
of specific drugs among which is carbamazepine, an antiepileptic agent. A very 
strong association of carbamazepine-induced SJS with HLA-B*1502 has recently 
been described in the Han Chinese population. Here in, we report preliminary 
results from a European study (RegiSCAR) of 12 carbamazepine-induced SJS/TEN 
cases (nine French and three German). Among these only four had a HLA-B*1502 
allele. Remarkably, these four patients had an Asian ancestry, whereas the 
others did not as far as we have ascertained. This shows that although the HLA 
region may contain important genes for SJS, the HLA-B*1502 allele is not a 
universal marker for this disease and that ethnicity matters.