We studied the distribution of laminin β2 chain in the skeletal muscle basement membrane of 16 patients with congenital muscular dystrophy (CMD) by immunohistochemistry. A dramatic reduction in the laminin β2 staining was observed in four patients with classical merosin-negative CMD. A moderate reduction of laminin β2 labelling was observed in four patients with partial merosin deficiency and two patients with merosin-positive CMD. Two patients with merosin-positive CMD had no apparent changes in the expression of laminin β2. In three patients and one fetus diagnosed as Walker-Warburg syndrome (WWS) the laminin β2 pattern was similar to normal controls. We conclude that a primary deficiency in the laminin α2 chain may lead to a vast or moderate reduction in the laminin β2 chain in the skeletal muscle membrane.
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