What kind of inheritance pattern does scid have?

Autosmal recessive: The genetic forms of severe combined immunodeficiency are caused by enzyme deficiencies, with affected individuals having two abnormal genes at the enzyme locus. Parents will have one normal and one abnormal gene with 50% enzyme activity (enough to produce immune cells). Parents will have a 25% risk for scid with each future pregnancy.

Depends on the type: The most common form of scid in the us is actually inherited in an x-linked fashion. That is, females are carriers of the disease; 50% of their male offspring are affected, while 50% of their female offspring will be carriers themselves. Affected males can only pass the gene to female children (who will be carriers). Other forms of scid are recessive, as discussed by others.