Table 4 Median and range Rett Syndrome Gross Motor Scale (RSGMS) scores and blood brain derived neurotrophic factor (BDNF) levels at each assessment by BDNF gene polymorphism (Val/Val, Val/Met, Met/Met)

N

Median (range)

N

Median (range)

N

Median (range)

N

Median (range)

N

Median (range)

 Val/Val

3

31

(30–34)

3

32

(30–33)

3

32

(30–35)

3

34

(32–37)

3

39

(30–39)

 Val/Met

7

16

(4–29)

7

16

(0–29)

7

23

(9–33)

7

24

(13–34)

7

26

(13–38)

 Met/Met

2

28.5

(27–30)

2

28.5

(27–30)

2

31.5

(30–33)

2

33.5

(33–34)

2

37.5

(36–39)

 Val/Val

3

173.8

(152.1–177.9)

3

166.6

(126.7–214.2)

–

–

–

–

3

493.1

(436.3–689.0)

 Val/Met

6^a

156.3

(117.5–232.6)

7

129.5

(69.8–211.4)

–

–

–

–

6^a

446.1

(387.1–619.6)

 Met/Met

2

172.39

(166.9–177.9)

2

147.5

(82.1–212.9)

–

–

–

–

1^a

566.7

(566.7–566.7)