Walker-Warburg syndrome (WWS) is an inherited condition causing a number of symptoms including muscle weakness, vision abnormalities, brain structure abnormalities, and severe developmental delay. The gene Counsyl tests for, FKTN, is also associated with a condition called Fukuyama congenital muscular dystrophy (FCMD), which has very similar symptoms to WWS.
WWS causes congenital muscular dystrophy, a form of muscle weakness that is present from birth or develops shortly after birth. It causes an infant to feel floppy in all of his or her muscles, including those of the face. He or she may also exhibit involuntary muscle jerks or twitches. Individuals with FCMD will experience similar symptoms at birth with most never being able to walk or stand.
Eye problems associated with WWS and FCMD can include blindness and cataracts, among others.
Another hallmark of WWS and FCMD is a brain abnormality known as cobblestone lissencephaly (or type II lissencephaly). The brain develops a bumpy "cobblestone" appearance and lacks the normal folding structure. Other structural changes in the brain are also present. These abnormalities lead to severe developmental delay and intellectual disability.
WWS is rare and the exact prevalence is unknown.
A survey performed in northeastern Italy reported an incidence of 1.2 per 100,000 live births for WWS. Approximately 1 in 150 individuals of Ashkenazi Jewish descent are carriers.
FCMD is rarely seen outside of individuals of Japanese descent where the incidence is 3.68 per 100,000 live births with a carrier frequency of approximately 1 in 83.
There is no successful treatment or cure for WWS or FCMD. Medical specialists can help treat specific symptoms, such as using medication to control seizures, placement of a shunt to reduce fluid buildup around the brain, tube feeding and physical and occupational therapy to aid in movement.
The prognosis for a child affected with WWS or FCMD is poor. WWS is both lethal and the severest form of congenital muscular dystrophy. Children affected with WWS typically die before 3 years of age. Individuals with FCMD typically live into late childhood or adolescence.
The CMD International Registry is a patient self-report registry with the goal to register the global congenital muscle disease population which includes congenital myopathy and congenital muscular dystrophy.
1712 Pelican Avenue
San Pedro CA 90732
Phone: (800) 363-2630
An all volunteer non-profit organization that funds research on congenital muscular dystrophies.
PO Box 701
Olathe KS 66051
Phone: (866) 400-3626
A consortium of non-profit organizations that raises awareness of genetic conditions common among Ashkenazi Jews.
450 West End Ave.
New York, NY 10024
Phone: (866) 370-4363