Elevated IL-10, vitamin B₁₂, and sFAS-L associated with FAS mutations. (A) IL-10 levels were determined from plasma samples by ELISA. Dashed line indicates upper normal limit at 20 pg/mL. (B) Vitamin B₁₂ plasma levels were determined by the National Institutes of Health Clinical Center laboratory. Dashed line indicates upper normal limit at 1000 pg/L. Upper limit of assay was 4000 pg/L. Results greater than 4000 pg/L were made to equal 4000 pg/L for analysis. (C) Soluble FAS-L levels were determined from plasma samples by ELISA. Dashed line indicates upper normal limit at 200 pg/mL. Long horizontal bars represent means; short horizontal bars, SE. *P < .05, **P < .01, compared with somatic or type Ia patients.