Inherited defects in components of purine catabolism and salvage are associated with various conditions and syndromes. The enzyme hypoxanthine-guanine (HGPRT) is a key enzyme in the purine salvage pathway. It is responsible for reforming IMP and GMP from hypoxanthine and guanine, respectively. In this manner purine bases are salvaged back into the purine nucleotide pool. Genetic defects that lead to the loss of HGPRT activity are the primary cause for which of the following conditions? a. Gout
b. Lesch-Nyhan syndrome
c. Orotic aciduria
d. Severe combined immunodeficiency syndrome
e. Tay-Sachs disease