Condition	Cause	Features similar to fetal alcohol syndrome	Distinguishing features from fetal alcohol syndrome
Aarskog syndrome	X-linked recessive, often mutations in FGD1, although others unknown	Broad philtrum, intellectual and neurobehavioral disabilities, small nose with anteverted nares, wide-spaced eyes	Brachydactyly, crease below lower lip, dental eruption problems, downward-slanting palpebral fissures, shawl scrotum (scrotum folds around penis), short stature that resolves with puberty, widow's peak
Bloom syndrome	Autosomal recessive chromosomal instability caused by mutation in BLM	Short stature with mild microcephaly, variably impaired intellectual ability	Café au lait spots; facial telangiectasia erythema; keel-shaped face; predisposition to early cancer, infertility, and immunodeficiency; sparse subcutaneous adipose tissue
Cornelia de Lange (Brachmann-de Lange) syndrome	Autosomal dominant from spontaneous mutations in NIPBL, RAD21, and SMC3, or X-linked dominant with mutations in HDAC8 or SMC1A	Anteverted nares, depressed nasal bridge, growth impairment, hearing loss, intellectual disability, microcephaly, short stature, smooth philtrum, thin vermilion border	Arched eyebrows that meet in the middle (synophrys), downturned mouth, high arched palate, hypertrichosis, long eyelashes, short limbs
Dubowitz syndrome	Unknown; suspected autosomal recessive	Neurobehavioral disabilities (hyperactivity, impulsivity, and inattentiveness), epicanthal folds, intellectual disability, microcephaly, short palpebral fissures, short stature, wide-spaced eyes	Broad nasal tip, cryptorchidism, eczema-like skin disorder, high-pitched voice, shallow supraorbital ridge with nasal bridge near level of forehead
Fetal hydantoin syndrome	Prenatal exposure to phenytoin (Dilantin)	Depressed nasal bridge, growth deficits, occasional intellectual disability, wide-spaced eyes	Genitourinary defects, hirsutism, hypoplastic fingertips, low hairline, orofacial clefts, short neck, short nose with bowed upper lip
Fetal valproate syndrome	Prenatal exposure to valproate (Depacon)	Anteverted nares, epicanthal folds, long philtrum, thin vermilion border, wide-spaced eyes	Cardiac malformations, high forehead, infraorbital crease, neural tube defects, small mouth
Noonan syndrome	Autosomal dominant, often mutation in PTPN11	Epicanthal folds, intellectual disability, low nasal bridge, short stature, wide-spaced eyes	Bleeding diathesis, cryptorchidism, downward-slanting palpebral fissures, hypertrophic cardiomyopathy, keratoconus, low posterior hairline, pectus excavatum, protruding upper lip, pulmonary stenosis, webbed neck, wide mouth
Phenylalanine embryopathy	Maternal phenylketonuria	Epicanthal folds, growth impairment, intellectual disability, long philtrum, microcephaly, short palpebral fissures, small nose with anteverted nares, thin vermilion border	Cardiac malformations, hypertonia, prominent glabella, round facies
Toluene embryopathy	Prenatal exposure to toluene	Growth deficits, midface hypoplasia, short palpebral fissures, smooth philtrum, thin vermilion border	Bifrontal narrowing of the skull, downturned mouth, ear abnormalities, hair pattern abnormalities, large anterior fontanelle, micrognathia
Velocardiofacial syndrome	Autosomal dominant with microdeletion in chromosome 22q11	Intellectual disabilities, psychiatric disorders, small palpebral fissures	Cardiac malformations, cleft palate, long face with prominent nose, transient neonatal hypocalcemia, weak pharyngeal muscles resulting in hypernasal speech
Williams syndrome	Heterozygous 7q11.23 deletion, including elastin gene	Anteverted nares, depressed nasal bridge, epicanthal folds, growth impairment, intellectual disability, long philtrum, short nose, short palpebral fissures	Aortic and pulmonary stenosis, connective tissue disorders, endocrine abnormalities, full lips, hoarse voice, hypertension, periorbital fullness, poor to near-normal language skills, renal abnormalities, stellate pattern of iris, systemic arterial stenosis, wide mouth