Table 2.

Characteristics of patients from whom newborn dried bloodspots were obtained

Patient	Current age (year)	Gender	Screen 1	Screen 2	Mutation 1	Mutation 2	Zygosity	GHB (urine)
1	10	F		x	p.W204*	p.R425*	CH	Elevated comparable to other patients
2	8	M	x		p.W204*	p.R425*	CH	Elevated comparable to other patients
2	8	M		x	p.W204*	p.R425*	CH	Elevated comparable to other patients
3	4	M	x		p.G533R	c.1015‐2A>Ca	CH	Elevated comparable to other patients
3	4	M		x	p.G533R	c.1015‐2A>Ca	CH	Elevated comparable to other patients
4	27	M	x		NA	NA		NA
5	8	F	x		p.M445L	c.610‐2A>G	CH	“Marked elevation”b
6	9	M	x		p.W204*	p.G441Rc	CH	79‐156 mmol/mol
7	5	F	x		c.104_127del p.Ser35*	c.1054‐2A>C	CH	“Marked elevation”
7	5	F		x	c.104_127del p.Ser35*	c.1054‐2A>C	CH	“Marked elevation”

Note: Patients 1 and 2 identical to patients 1 and 2 in Table 1; for urine GHB, control values are <9 mmol/mol creatinine.

Abbreviations: CH, compound heterozygous; HZ, homozygous.

^aSplice site SNP [1] at the intron 6/exon 7 junction.14, 21.

^bIn addition to elevated 4‐hydroxybutyric acid, the urine organic acids revealed elevations of 4,5‐dihydroxyhexanoic, glutaric, adipic, glycolic, 3‐hydroxypropionic, and 2‐hydroxyglutaric acids, all hallmarks of SSADH deficiency, in two unique urine samples.22, 23

^cPolyPhen characterization of p.G441R indicated a strong likelihood of pathogenicity.