Structural (betaalpha)8 TIM barrel model of 3-hydroxy-3-methylglutaryl-coenzyme A lyase. This study describes three novel homozygous missense mutations (S75R, S201Y, and D204N) in the 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) lyase gene, which caused 3-hydroxy-3-methylglutaric