Case: Male, born at 38 weeks gestation

DiseaseAssertion: Hypertrophic Cardiomyopathy

CasePresentingHPOs: HP:0030718, HP:0001667, HP:0002092, HP:0001670, HP:0200128 (enlarged right atrium, right ventricular hypertrophy, pulmonary hypertension, asymmetric septal hypertrophy, biventricular hypertrophy)

CaseHPOFreeText: birth weight = 3.283kg, apgar scores = 8,9, asymmetric septal hypertrophy of atrioventricular septum without outflow tract obstruction or myocardial scarring, confirmed diagnosis of HCM at 6mo

CaseNotHPOs: HP:0011611, HP:0001653, HP:0004308, HP:0005115 (aortic obstruction, mitral valve insufficiency, ventricular arrhythmia, supraventricular arrhythmia)

FamilyInfo: Both parents and only sibling underwent genetic testing, the father and brother harbored the same variant as the patient (p.Ala1328Thr), this variant was absent in the mother. Father (36yo) and brother (5yo) had normal echocardiograms.

CasePreviousTesting: fetal echocardiography at 32wks, postnatal echocardiography, routine cardiac follow-up at 6mo, cardiac MRI, 24hr Holter monitor, Full testing (MYBPC3, TNNT2, TNNI3, MYL2, MYL3, TPM1, ACTC1), Additional testing (CAV3, MTTG, MTTI, MTTK, MTTQ, TNNC1, TTR, PKRAG2, LAMP2, GLA)

CaseGenotypingMethod: blood and buccal cell samples collected from patient, coding regions and splice junctions of 18 genes were enriched with a proprietary targeted capture system by GeneDx, these then underwent NextGen sequencing, capillary sequencing used to confirm potentially pathogenic variants

Variant: NM_000257.3(MYH7):c.3982G>A (p.Ala1328Thr)

ClinVar: 42985, https://www.ncbi.nlm.nih.gov/clinvar/variation/42985/

gnomAD: 0.00002154, https://gnomad.broadinstitute.org/variant/14-23887606-C-T

InheritancePattern: autosomal dominant