G818EER51 ± 1363 ± 5111 ± 825 ± 312 ± 32Moderate/Severe
When expressed in transfected HEK293T cells and quantified by Western blotting, this variant was in the range of 40%-52%. This variant has a basal ATPase activity of 63% ± 5% compared to WT (100%) and was categorized as class 2 (partial reduction in expression and basal ATPase activity that was modestly stimulated by N-Ret-PE) with a moderate/severe predicted severity.