RESUMO
Family trio next-generation sequencing-based variant analysis was done to identify the genomic reason on unexplained recurrent pregnancy loss (RPL). A family (dead fetus and parents) from Saudi Arabia with an earlier history of three unexplained RPLs at the ninth week of pregnancy was included in the study. Whole-genome sequencing (WGS) of a dead fetus and the parents was done to identify the pathogenic variation and confirmed through Sanger sequencing. WGS of dead fetus identifies a novel homozygous exonic variation (NM_017419.3:c.680G>T) in ASIC5 (acid-sensing ion channel subunit family member 5) gene; the parents are heterozygous. Newly designed ARMS PCR followed by direct sequencing confirms the presence of heterozygous in one subject and absence of homozygous novel mutation among randomly selected healthy Saudis. The second family with heterozygous was confirmed with three unexplained RPLs. Pathogenicity analysis of R227I amino acid substitution in ASIC5 protein through molecular docking and interaction analysis revealed that the mutations are highly pathogenic, decrease the stability of the protein, and prevent binding of amiloride, which is an activator to open the acid-sensing ion channel of ASIC5. The identified rare and novel autosomal recessive mutation, c.680G>T:p.R227I (ASIC5Saudi), in two families confirm the ASIC5 gene association with RPL and can be fatal to the fetus.
RESUMO
The prevalence of consanguineous marriage and genetic disorders are high in Saudi Arabia. There were records on the practices of Saudis toward prenatal diagnosis (PND) and termination of pregnancy (TOP), however the sample sizes are small. This study has targeted the Saudi Arabian community and family history of genetic disorders to determine the practices toward PND and TOP. The cross-sectional survey was conducted among Saudis (n = 2761) to determine their practices toward reproductive-decision making. Regression analysis was conducted to identify the association of the limiting factors, relative merits and family history on the outcomes. Total of 2507 participants returned completed questionnaire. The practice towards PND (68%) were more favorable than TOP (33%). PND was found to be a good opportunity for early diagnosis and gives parent's choice. Education, history with affected baby, prior knowledge and religious belief were significant deciding factors of PND and TOP. Down syndrome (n = 161) and sickle cell anemia (n = 152) were commonly available genetic disorder among participant's family. Respondents with autistic cases in their family have higher acceptance rate for TOP. Non-consanguineous are more willing to consider TOP than consanguineous. Participants with abnormal fetus, aged of > 36 years, married and educated Saudis were more likely consider TOP. Though, religion is the most influencing factor for not accepting TOP, comparatively willingness to PND and TOP have increased recently. Awareness campaigns about PND and TOP may increase the chances of accepting prenatal genetic diagnosis.