Medicina (Oct 2022)

PIGN-Related Disease in Two Lithuanian Families: A Report of Two Novel Pathogenic Variants, Molecular and Clinical Characterisation

  • Evelina Siavrienė,
  • Živilė Maldžienė,
  • Violeta Mikštienė,
  • Gunda Petraitytė,
  • Tautvydas Rančelis,
  • Justas Dapkūnas,
  • Birutė Burnytė,
  • Eglė Benušienė,
  • Aušra Sasnauskienė,
  • Jurgita Grikinienė,
  • Eglė Griškevičiūtė,
  • Algirdas Utkus,
  • Eglė Preikšaitienė

DOI
https://doi.org/10.3390/medicina58111526
Journal volume & issue
Vol. 58, no. 11
p. 1526

Abstract

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Background and Objectives: Pathogenic variants of PIGN are a known cause of multiple congenital anomalies-hypotonia-seizures syndrome 1 (MCAHS1). Many affected individuals have clinical features overlapping with Fryns syndrome and are mainly characterised by developmental delay, congenital anomalies, hypotonia, seizures, and specific minor facial anomalies. This study investigates the clinical and molecular data of three individuals from two unrelated families, the clinical features of which were consistent with a diagnosis of MCAHS1. Materials and Methods: Next-generation sequencing (NGS) technology was used to identify the changes in the DNA sequence. Sanger sequencing of gDNA of probands and their parents was used for validation and segregation analysis. Bioinformatics tools were used to investigate the consequences of pathogenic or likely pathogenic PIGN variants at the protein sequence and structure level. Results: The analysis of NGS data and segregation analysis revealed a compound heterozygous NM_176787.5:c.[1942G>T];[1247_1251del] PIGN genotype in family 1 and NG_033144.1(NM_176787.5):c.[932T>G];[1674+1G>C] PIGN genotype in family 2. In silico, c.1942G>T (p.(Glu648Ter)), c.1247_1251del (p.(Glu416GlyfsTer22)), and c.1674+1G>C (p.(Glu525AspfsTer68)) variants are predicted to result in a premature termination codon that leads to truncated and functionally disrupted protein causing the phenotype of MCAHS1 in the affected individuals. Conclusions: PIGN-related disease represents a wide spectrum of phenotypic features, making clinical diagnosis inaccurate and complicated. The genetic testing of every individual with this phenotype provides new insights into the origin and development of the disease.

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