Table 3.

Possible effects of genotype and environmental factors on patient response to pyridoxine, prematurity and developmental outcome

Group	Patient	Genotype	Born prematurely	Ethnicity	Mother given B6	Neonatal feeding	Seizure onset	Time taken to control seizures	Response to PN	Current age	Outcome
(i)	1	R95H + E50K;Splice errorsa	+	Asian		?	30 min	5 d	-	2 y 8 m	Global delay
	2	D33V/D33V	-	Caucasian		B	6 h	8 w	-	4 y	Normal
	3	P213S/P213S	-	Caucasian		B/F*	90 min	3–6 d	-	2 y 7 m	Normal
	4**	P213S/P213S	+	Caucasian	+	F	None	No seizures	Not tried	4 m	Normal
	5	R95C/R95C	+	Turkish		F	2 h	7 d	Not tried	1 y	IQ 66 at 9 m. Mild truncal hypotonia and speech delay
	6d	Q214fs/?	+	Caucasian		PN/F	5 h	15 d	-	4 y	Normal
(ii)	7	R116Q/R116Q	?	Caucasian		B	5 m	24 h	-	4 y	Normal/advanced
(iii)	8	R116Q/R116Q	-	Pakastani		?	3 h	2.5 m	+	7 y	Mild learning disability
	9	D33V/D33V	-	Caucasian		F	3 w	1 w	+	2 y	Minimal delay
	10	D33V/E120K	?	Caucasian		?	2 m	4 m	+	21 y	Mild intellectual disability
	11	D33V/Splice errors	+	Caucasian		F	3 h	6 m	+	21 y	Severe delay/no language
	12	D33V + R225C + R116Qb	-	Caucasian		F	14 d	3.5 m	+	41	IQ 93. Dyslexia and Aspergers
	13	R225H/R225H	?	?		?	24 h	6 m	+	7 y	Spastic quadriplegia with good social contact
	14	R225H;R116Q + R225H;R116Qc	-	Caucasian		?	30 min	2 w	+	2 y 7 m	Minimal delay
	15	R225H;R116Q + R225H;R116Qc	+	Kosovan		?	10 h	5 d	+	8 y	DQ 65

(i) Neonatal onset seizures responding to pyridoxal 5’-phosphate.

(ii) Infantile spasms (onset 5 months) responsive to pyridoxal 5’-phosphate.

(iii) Seizures starting under 3 months of age responding to pyridoxine.

B = breast-fed; F = formula fed; PN = parenteral nutrition; – = no; + = yes

*Formula from 2 weeks

**Sibling of Patient 3.

^ac.[148G>A] and c.[364-1G>A] were inherited in cis, this was confrimed by analysing parental DNA.

^bNo parental DNA was available to ascertain which muation R116Q was in cis with.

^cAssume that R116Q has been inherited in cis with R225H, no parental DNA was available to confirm this.

^dSecond mutation not found.