Targeted next-generation sequencing reveals two novel mutations of NBAS in a patient with infantile liver failure syndrome-2

Mutations in neuroblastoma amplified sequence (NBAS) cause infantile liver failure syndrome-2 (ILFS2). NBAS is a protein involved in Golgi‑to‑endoplasmic reticulum retrograde transport. Exon capture in combination with high‑throughput sequencing was used to detect NBAS mutations. Via targeted sequencing, two causative mutations were identified from 358 selected genes associated with growth and development diseases; one was a missense mutation, c.3596G>A (p.C1199Y), detected in the coding region of NBAS (NM_015909.3), and the other a splice site mutation, c.209+1G>A. Both of these were heterozygous. The SEC39 structure of the wild‑type NBAS protein was compared with a model of the mutated protein. The overall structure of the SEC39 after mutation did not change; however, steric hindrance did increase. In conclusion, two novel NBAS mutations were identified in a 4‑year‑old Chinese girl with ILFS2.