A parent is homozygous and a parent heterozygous for an autosomal recessive gene. What will be the outcome –
75% children affected
No child affected, but all are carriers
50% children affected, rest are carriers
25% children affected, rest are carriers
Autosomal recessive disorders 

Autosomal recessive disorders are manifested in homozygous state, i.e. when both alleles at a given gene locus are mutant.
There may be following five situations -