Ashy ears.

Alkaptonuria is a rare, autosomal-recessive disease of tyrosine degradation resulting from accumulation of homogentisic acid (HGA) within the body due to deficiency of the hepatic enzyme homogentisate 1,2-dioxygenase[1]. HGD is the gene encoding homogentisate 1,2-dioxygenase and is the only gene known to be associated with alkaptonuria. In this patient the disease also manifested itself with symmetric blue-gray discoloration on the helix cartilage of his ears.