ABSTRACT
Objective@#To analyze and summarize the clinical and molecular characteristics of the patients with multiple congenital anomalies- hypotonia-seizures syndrome 1 (MCAHS 1).@*Method@#Clinical data and test results were collected from a patient who was diagnosed with confirmed genetic basis of MCAHS 1 in Shanghai Children′s Medical Center since December 2015. The patient and his parents were examined by the next generation sequencing (NGS) technology using peripheral blood genomic DNA, and the relevant mutations identified by NGS were verified with Sanger sequencing. Related literature was searched from PubMed and Embase databases (from their establishment to January 2017) by using "PIGN gene" as a keyword, the retrieved articles were further reviewed for the clinical manifestations, results and prognosis of PIGN related variants.@*Result@#A nearly 4-month-old Chinese boy was presented with epilepsy, hypotonia, developmental delay, accompanied by nearly normal laboratory test results. The NGS analysis revealed a compound heterozygous variations in the PIGN gene, included a known splice site mutation (c.963G>A) which was inherited from his father, and a novel nonsense mutation (c.2773A>T, p.Lys925*) which was inherited from his mother. Nine associated articles were retrieved. Including our patient, a total of 22 cases were identified as the PIGN variants. The most common clinical manifestations were developmental delay, hypotonia, and epilepsy.Missense varients were most frequently found. Prognosis was poor. Eight cases died, while survived cased suffered from refractory epilepsy, profound mental retardation, muscle weakness, etc.@*Conclusion@#MCAHS1 is characterized by epilepsy, severe developmental delay, hypotonia, and may be accompanied by multiple malformations of other systems. Homozygous or compound heterozygous variants in PIGN gene are the cause of the disease.