<s>[INST] <<SYS>> This is a medical question of type : frequency <</SYS>> How many people are affected by ALG6-congenital disorder of glycosylation ? [/INST] The prevalence of ALG6-CDG is unknown, but it is thought to be the second most common type of congenital disorder of glycosylation. More than 30 cases of ALG6-CDG have been described in the scientific literature. </s>