Implementation of second-tier tests in newborn screening for the detection of vitamin B12 related acquired and genetic disorders: results on 258,637 newborns

Table 2 Altered biomarkers in genetic and acquired conditions

Biomarkers	Genetic conditions		Acquired conditions
Biomarkers	N/total N	Percentage %	N/total N	Percentage %
(A) Primary biomarkers
C3	17/21	80	117/144	81
C3/C2	14/21	67	32/144	22
C3/Met	12/21	57	24/144	17
C17	9/21	43	17/144	12
Low Met	2/21	9.5	10/144	7
High Met	3/21	14	2/144	1.4
(B) Second-tier test biomarkers*
MMA	11/19	58	78/130	60
Hcys	9/19	47	113/130	87
MCA	10/19	53	6/130	5

C3 propionylcarnitine, C2 acetylcarnitine, Met Methionine, C17 heptadecanoylcarnitine, MMA methylmalonic acid, Hcys homocysteine, MCA methylcitric acid, N number of diagnosed cases with altered biomarker, total N total number of diagnosed cases

ISSN: 1750-1172