A. Ability to walk

1. E-Figure 2: Relationship between RTT phenotype and MECP2 genotype. Clinical severity in three clinical features (A, ability to walk; B, psychomotor development during the first year; and C, onset of seizures) depends on specific MECP2 mutations. There is an overall difference in the severity of these clinical manifestations (A, p=0.01; B, p=0.03; C, p=0.03) between different MECP2 mutations. NS, Non-sense. MS, Missense. LT, Large truncating. ID, Interdomain. B. Psychomotor development during the first year A. Ability to walk Scale of severity Scale of severity 0 1 2 0 1 2 Large deletion (n=4) Large deletion (n=4) R255X (n=5) R255X (n=6) R270X (n=9) R270X (n=9) R294X (n=6) R294X (n=6) R168X (n=9) R168X (n=9) Other NS mutations (n=4) Other NS mutations (n=4) LT mutations (n=9) LT mutations (n=9) R306C (n=8) R306C (n=8) R133C (n=2) R133C (n=2) T158M (n=7) T158M (n=7) Other MS mutations (n=12) Other MS mutations (n=12) 0 10 20 30 40 50 60 70 80 90 100 0 10 20 30 40 50 60 70 80 90 100 Percent Percent C. Onset of seizures Scale of severity 0 1 2 Large deletion (n=5) R255X (n=6) R270X (n=9) R294X (n=6) R168X (n=6) Other NS mutations (n=4) LT mutations (n=11) R306C (n=8) R133C (n=2) T158M (n=7) Other MS mutations (n=4) 0 10 20 30 40 50 60 70 80 90 100 Percent