We are indebted to the families who participated in this study. We thank CERCA Program/Generalitat de Catalunya for institutional support. We thank Cristina Guilera and Juanjo Martínez for excellent technical assistance at Neurometabolic Diseases Lab. We thank the Mayo Clinic Mitochondrial Disease Center for excellent support. This study was supported by the Centre for Biomedical Research on Rare Diseases (CIBERER) [ACCI14-759], [ACCI19-26], the URDCat program (PERIS SLT002/16/00174), the Fondo de Investigación Sanitaria FIS PI17/00916 (ISCIII) (co-funded by European Regional Development Fund. ERDF, a way to build Europe), the Hesperia Foundation, and the Secretary for Universities and Research of the Ministry of Business and Knowledge of the Government of Catalonia [2017SGR1206] to AP. AGC and NJP were funded by Fondo de Investigación Sanitaria (FIS) P118/00111 (Instituto de Salud Carlos III: ISCIII and “Fondo Europeo de desarrollo regional” FEDER). RA was funded by FIS PI17/00109 (ISCIII). EV was funded by grants from the Ministerio de Economia, Industria y Competividad (Juan de la Cierva program FJCI-2016-28811) and Instituto de Salud Carlos III (Sara Borrell program, CD19/00221). SF was funded by the Instituto de Salud Carlos III [Miguel Servet program CPII16/00016, co-funded by European Social Fund. ESF investing in your future]. MR was funded by CIBERER. LPS and AJP were funded by predoctoral grants from the Instituto de Salud Carlos III (PFIS, FI18/00141 and FI18/00253). EK and MC were funded by the Center for Individualized Medicine at Mayo Clinic. ET and CF were funded by a grant from the NIH (HL121079), the Anne Dash Weinman Fund in Cardiovascular Research Honoring Steven J. Lester, and the Nasser Al-Rashid Fund for Research in Cardiovascular Diseases. AP and EWK are members of the Undiagnosed Diseases Network International (UDNI). We are indebted to the “Biobanc de l’Hospital Infantil Sant Joan de Déu per a la Investigació” integrated in the Spanish Biobank Network of ISCIII for the sample and data procurement of patient 3. MZ and ND were supported in part by The Linda T. and John A. Mellowes Endowed Innovation and Discovery Fund and the Genomic Sciences and Precision Medicine Center of Medical College of Wisconsin.
SHMT2 Working Group: Alfonso Oyarzábal, Inés Medina, Aida Ormazábal, Jordi Muchart, Juan Manuel Carretero, Cristina Jou, Mireia del Toro, Andrés Nascimento, Abraham J. Paredes, Delia Yubero, Roser Colomé. Neurometabolic Unit and Synaptic Metabolism Lab, Neurology Department, Institut Pediàtric de Recerca, Hospital Sant Joan de Déu, and MetabERN, 08950, Barcelona, Catalonia, Spain: AlOy, IM, AiOr, JM, JMC, RC. Centre for Biomedical Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029, Madrid, Spain: AlOy, AiOr, CJ, AJP, DY, RC. Pathology Department, Institut de Recerca Sant Joan de Déu, and MetabERN, 08950, Barcelona, Catalonia, Spain: CJ. Pediatric Neurology Department, Vall d’Hebron University Hospital, Universitat Autònoma de Barcelona, 08916, Barcelona, Spain: MdT. Neuromuscular Unit, Neurology Department, Institut Pediàtric de Recerca, Hospital Sant Joan de Déu, 08950, Barcelona, Catalonia, Spain: AN. Clinical Biochemistry and Genetics Departments, Institut de Recerca Sant Joan de Déu, and MetabERN, 08950, Barcelona, Catalonia, Spain: AJP, DY.