Table 1. CHDs and associated genetic syndromes.

Genetic abnormality	Genetic test	Type of CHD	% Affected by CHD	Associated genes
Trisomy 21	FISH CMA	ASD, VSD, AVCD, TOF	40–50	3rd copy of chromosome 21; unbalanced translocation
Trisomy 13	FISH CMA	ASD, PDA, VSD, pulmonary atresia with CHD	60–80	3rd copy of chromosome 13; unbalanced translocation
Trisomy 18	FISH CMA	ASD, VSD, PDA, CoA, bicuspid aortic valve, complex CHD	60–80	3rd copy of chromosome 18
Monosomy X (Turner syndrome)	FISH CMA	CoA, BAV, AS, partial anomalous pulmonary, venous return, HLHS	23–50	Partial or incomplete absence of 1 X chromosome 45X
DiGeorge syndrome (chromosome 22q11.2 deletion)	FISH, CMA	IAA type B, aortic arch anomalies, truncus, arteriosus, TOF	70–75	22q11.2 deletion
Noonan syndrome	Noonan gene panel	PS, hypertrophic CM, ASD	70–80	RAS-MAPK pathway (KRAS, SOS1, RAF1, NRAS, BRAF, SCHOC2, CBL, RIT1)
Alagille syndrome	CMA	PS, TOF	90	JAG1, NOTCH2
Holt-Oram syndrome	Molecular testing	HCM	75	TBX5

Abbreviations: AVCD, atrioventricular canal defect; ASD, atrial septal defect; BAV, bicuspid aortic valve; CHD, congenital heart disease; CM, cardiomyopathy; CMA, chromosomal microarray; CoA, coarctation of the aorta; HCM, hypertrophic cardiomyopathy; PDA, patent ductus arteriosus; PS, pulmonic stenosis; TOF, tetralogy of Fallot; VSD, ventricular septal defect.