Why does wiskott aldrich syndrome only affect males?

Genetic disease: It is a genetic disorder which is transmitted on the y-chromosome. Males(boys) have xy chromosomes and females (girls have xx chromosome).

X-linked disease: The gene associated with this condition is located on the x chromosome, which is one of the two sex chromosomes. In females (who have two x chromosomes), a mutation in one of the two copies of the gene in each cell usually does not cause the disorder. In males (who have only one x chromosome), a mutation in the only copy of the gene in each cell causes the disorder.