EFNB1

Clinical Characteristics

Classic presentation occurs in heterozygous females with midline defects, as severe hypertelorism, a grooved nasal tip and unilateral or bilateral coronal craniosynostosis.
As well as some variable but frequent manifestations, such as frizzy hair, cleft lip and/or palate, Sprengel anomaly, partial syndactyly of the hands and feet and longitudinal ridging of the nails.
Therefore, some extracranial not midline defects have been described too, as they might present with cardiac, abdominal, and genitourinary anomalies as well.

Females:

Head
•    Brachycephaly
•    Plagiocephaly

Face
•    Frontal bossing
•    Facial asymmetry
•    Widow’s peak

Eyes
•    Hypertelorism
•    Telecanthus
•    Exotropia
•    Nystagmus
•    Strabismus
•    Downslanting palpebral fissures
•    Ocular melanosis (one patient)

Nose
•    Bifid nasal tip
•    Hypoplastic nasal tip

Mouth
•    Cleft lip
•    Cleft palate

Neck
•    Short neck

Chest
•    Narrow sloping shoulders
•    Sprengel deformity
•    Scoliosis
•    Pectus excavatum
•    Unilateral breast hypoplasia

Heart
•    Atrial septal defect
•    Bicuspid aortic valve
•    Ventricular septal defect
•    Hypertrophic cardiomyopathy
•    Wolff-Parkinson-White syndrome

Abdomen
•    Umbilical hernia
•    Congenital diaphragmatic hernia

Genitourinary
•    Uterus didelphys
•    Duplex kidney
•    Septate vagina

Skull
•    Coronal craniosynostosis (uni or bilateral)

Limbs
•    Asymmetric lower limb shortness
•    Joint laxity

Hands
•    Syndactyly
•    Brachydactyly
•    Fifth finger clinodactyly

Feet
•    Syndactyly
•    Broad halluces

Skin
•    Axillary pterygia

Nails
•    Brittle nails
•    Longitudinal splitting
•    Grooved nails

Hair
•    Thick, wiry hair
•    Widow’s peak
•    Low posterior hairline

Neurologic
•    Developmental delay
•    Hypotonia
•    Hypoplasia or agenesis of corpus callosum

Males present with a less severe phenotype, sometimes showing only mild clinical features such as hypertelorism. Some others, present with congenital diaphragmatic hernia, but without other distinctive anomalies, as in females.

Males (might present with only one of the features):
•    Mild clinical features

Height
•    Short stature

Head
•    Brachycephaly
•    Frontal bossing
•    Thick, wiry hair

Face
•    Hypertelorism

Hands
•    Brachydactyly

Abdomen
•    Congenital diaphragmatic hernia

Genitourinary
•    Hypospadias
•    Shawl scrotum
•    Cryptorchidism