Walker-Warburg Syndrome (WWS) or Muscle-Eye-Brain (MEB) Disease is a brain, eye, and muscle, birth defect that includes abnormalities of the Cerebellum (the part of the brain that is located in the lower back part of the head and controls coordination, cauliflower in appearance), Lissencephaly (cobblestone, granular, or pebbled surface of the brain), Hydrocephalus (water-on-the-brain) and/or Encephalocele or Meningocele (hole in skull) or meningoencephalocele, Polymicrogyria, Agenesis (absence) of Corpus Collasum (ACC) or partial ACC, eye abnormalities (retinal, detached retina, glacoma, cataracts, microphthalmia (small eye), etc), and a muscle disease (Congenital Muscular Dystrophy). This group also welcomes those with only Cobblestone Lissencephaly (CLO), where there is no eye or muscle abnormalities. And, this list welcomes those with Fukuyama Congenital Muscular Dystrophy (FCMD), the Japanese version of this disorder.
Warburg Micro syndrome (WARBM1) is a severe autosomal recessive disorder characterized by developmental abnormalities of the eye and central nervous system and by microgenitalia. They’ve identified homozygous inactivating mutations in RAB3GAP, encoding RAB3 GTPase activating protein, a key regulator of the Rab3 pathway implicated in exocytic release of neurotransmitters and hormones.
More information on these syndromes can be found on the Lissencephaly Network web site at http://www.lissencephaly.org and at the Lissencephaly List at http://egroups.yahoo.com/group/lissencephaly or at the Lissencephaly Launchpad: http://homepage.ntlworld.com/foliot/liss
MEB maps to chromosome 1p34-p32, POMGnT1 gene. MEB patients show decrease in protein O-MANNOSE BETA-1,2-N-ACETYLGLUCOSAMINYLTRANSFERASE. WWS maps to chromosome 9q34.1, POMT1 gene, and POM2 gene (14q24.3). FCMD maps to 9q31, FKRP and Fukutin genes maps to 19q13.3 Micro Syndrome maps to 2q21.3
MEB/WWS - gene mutations in major basement membrane protein, collagen IV alpha 1 (COL4A1).