Major criteria:
(1) congenital sensorineural hearing loss
(2) pigmentary disturbance of the iris
(3) hair hypopigmentation, with a white forelock
(4) dystopia canthorum, with the average W index (see next section) for affected family members >= 1.95
(5) affected first degree relative
Pigmentary disturbance of the iris may be either:
(1) complete heterochromia iridum (2 eyes of different colors)
(2) partial or segmental heterochromia, with segments of blue or brown pigmentation in one or both eyes
(3) hypoplastic blue eyes, with both eyes showing a characteristic brilliant blue color
Minor criteria:
(1) congenital leukoderma with several areas of hypopigmented skin
(2) synophyrys or medial eyebrow flare
(3) broad and high nasal root
(4) hypoplastic alae nasi
(5) premature greying of hair, with scalp hair predominantly white before age 30
An affected person should have one of the following:
(1) >= 2 major criteria
(2) >= 1 major and >= 2 minor criteria
For Type 2 disease the person should show both of the following:
(1) >= 2 major criteria
(2) have a first degree relative with >= 2 major criteria
where:
• Having a first degree relative affected is major criteria number 5. It would seem that both the patient and first degree relative would need to have 2 major criteria in addition to this one.
