Crucial role of preserving umbilical cord stumps for genetic decoding of a family with rhabdoid tumor predisposition syndrome.

BACKGROUND

The Rhabdoid tumor is an aggressive tumor that is commonly found in infants and children with a prevalence of about, 0.6 in every 1 million children. The SMARCB1 or SMARCA4 gene mutations can result in Rhabdoid tumor predisposition syndrome 1 and 2 respectively. In Indian customs, dried umbilical cord stumps that had fallen off were stored to treat various illnesses, including infertility.

AIM AND

OBJECTIVE

This study aims to unravel the mystery behind recurrent childhood loss in a family using umbilical cord stumps of the deceased children.

METHODOLOGY: We obtained the dried umbilical cord stumps of the deceased children, which were stored by their parents, as there was no genetic diagnosis performed on the children who passed away unexpectedly. Following DNA extraction from the parents' and the umbilical cord stumps, whole exome sequencing analysis (WES) was performed.

RESULTS

The WGS report showed a pathogenic germline mutation, Chr22:g.23791780; c.118C > T; (p.Arg40Ter) in the SMARCB1 gene causing Rhabdoid tumor predisposition syndrome 1, which was present in the children who passed away earlier. The mother was discovered to be a silent carrier with heterozygous mutant alleles, according to carrier screening and segregation analysis. Genetic counseling was given to the parents in light of the 50 % recurring risk in the foetus, and the continued pregnancy was determined to be normal. The diagnostic benefit of using dried umbilical cord stumps which are customarily retained by Indian parents who have had early childhood losses was demonstrated by this investigation.