<unk>  has historically been estimated to occur in roughly one in every 20,000 live births, but more recent epidemiological studies have placed the occurrence rate at closer to one in every 7,500 live births, a significantly larger prevalence. As increasing evidence suggests<unk>  is more common than originally noted (about 6% of all genetic cases of developmental disability), researchers have begun to theorize past underdiagnosis of the syndrome. One theorized reason for the increase in epidemiological estimates is that a substantial minority of individuals with the genetic markers of<unk>  syndrome lack the characteristic facial features or the diminished intelligence considered to be diagnostic of the syndrome, and often are not immediately recognized as having the syndrome.
Williams syndrome
Noonan syndrome
Wolfram syndrome
DiGeorge syndrome
Kaufman oculocerebrofacial syndrome
Fetal alcohol spectrum disorder
GAPO syndrome
Muenke syndrome