The Klippel–Trenaunay–Weber syndrome (KTWS) is generally
thought to occur sporadically,
following a somatic mutation model. However, in some cases, clinical manifestations
of the syndrome
have been found in family members, suggesting an autosomal dominant inheritance.
Here we present
an epidemiological analysis of a consecutive series of cases with KTWS
identified in the Spanish
Collaborative Study of Congenital Malformations (ECEMC). We found an increase
in parental age
and in the number of pregnancies, as well as familial occurrence of haemangiomas.
observations suggest a genetic contribution to the occurrence of KTWS.