A novel homozygous mutation in the PADI6 gene causes early embryo arrest

Reprod Health. 2022 Sep 10;19(1):190. doi: 10.1186/s12978-022-01495-7.

Abstract

Background: It has been proved that mutations in the PADI6 gene can cause early embryo arrest. This study describes a newly discovered mutation in PADI6 that expands the genetic spectrum of early embryo arrest.

Methods: Peripheral blood of a patient diagnosed with early embryo arrest was collected for whole-exome sequencing. Sanger sequencing was performed to confirm this mutation. The effects of the variant were investigated in human embryonic kidney 293T (HEK293T) cells using western blotting, real-time quantitative polymerase chain reaction, and immunofluorescence.

Results: A novel homozygous mutation in PADI6 was identified in the proband. The patient carried a frameshift insertion mutation c.558dupA (p.Thr187Asnfs*48), which was located in the protein arginine deiminase middle domain. The variant destroyed PADI6 protein expression and reduced PADI6 mRNA expression in HEK293T cells.

Conclusions: The newly identified mutation in PADI6 accounts for early embryo arrest. It expands the spectrum of genetic causes and phenotypes of infertility in humans. These findings also provide an additional possible diagnostic marker for patients with recurrent in vitro fertilization/intracytoplasmic sperm injection failure.

Keywords: Early embryo arrest; Infertility; Mutation; Peptidylarginine deiminase type VI; Subcortical maternal complex.

Plain language summary

Some infertile patients experience multiple in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) failure owing to recurrent early embryo arrest. However, the underlying mechanisms remain largely unknown. Due to the development of whole-exome sequencing, early embryo arrest has been confirmed as a type of Mendelian disease. This study aimed to identify the genetic cause of early embryo arrest in patients and to expand the genetic spectrum. Furthermore, it can help doctors offer better suggestions to such patients and prevent patients from suffering from multiple IVF/ICSI failures.

MeSH terms

  • Embryonic Development*
  • Female
  • HEK293 Cells
  • Homozygote
  • Humans
  • Infertility / genetics*
  • Mutation
  • Protein-Arginine Deiminase Type 6 / genetics*

Substances

  • PADI6 protein, human
  • Protein-Arginine Deiminase Type 6