Classification of mutants on the basis of their “in vitro” altered properties and the associated clinical phenotypes.

a++: highly conserved; + conserved in vertebrates; − not conserved.baccording to Palmai et al. [9].ccatalytic efficiency toward 3-PG or MgATP: +++ dheat stability (T50): +++ nearly 10°C lowered; ++ nearly 3–7°C lowered; + nearly 2°C lowered; − comparable to wild-type.A: anemia (+/−: compensated hemolytic anemia with occasional hemolytic crises); M: muscular disorders after physical exercises; N: neurological disorders.