This particular kid has a condition called a congenital disorder of glycosylation. There are 100+ types of CDG, some of them incredibly rare. All are caused by a genetic mutation which results in an enzyme defect preventing glycosylation, which is just adding long chains of sugar molecules, called glycans, to a protein or lipid. If an enzyme is missing, the body can't modify a given lipid or protein in this way, and it fucks everything up. Most of the congenital disorders of glycosylation present with severe symptoms affecting multiple body systems, particularly the brain. I'm some of the subtypes, life expectancy is significantly shortened.
The most common type of CDG is called PMM2-CDG or PMM2 deficiency, caused by a mutation in the gene PMM2, which encodes an enzyme called phosphomanommutase 2.
Anyway, you're right about the profoundly retarded, anyway. I don't really have a problem with choosing rainbow earmolds for a kid who can't choose for himself. It doesn't make him gay, and he's not going to troon out.