Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2
The ENST00000706887.1(MADD):c.508C>T(p.Arg170Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000434 in 1,614,106 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R170H) has been classified as Uncertain significance.
MADD (HGNC:6766): (MAP kinase activating death domain) Tumor necrosis factor alpha (TNF-alpha) is a signaling molecule that interacts with one of two receptors on cells targeted for apoptosis. The apoptotic signal is transduced inside these cells by cytoplasmic adaptor proteins. The protein encoded by this gene is a death domain-containing adaptor protein that interacts with the death domain of TNF-alpha receptor 1 to activate mitogen-activated protein kinase (MAPK) and propagate the apoptotic signal. It is membrane-bound and expressed at a higher level in neoplastic cells than in normal cells. Several transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Jul 2008]
Verdict is Uncertain_significance. Variant got 2 ACMG points.
PM2
?
PM2 - Absent from controls (or at extremely low frequency if recessive) in Exome Sequencing Project, 1000 Genomes Project, or Exome Aggregation Consortium
Very rare variant in population databases, with high coverage;
Uncertain significance, criteria provided, single submitter
clinical testing
Ambry Genetics
Oct 03, 2022
The c.508C>T (p.R170C) alteration is located in exon 3 (coding exon 2) of the MADD gene. This alteration results from a C to T substitution at nucleotide position 508, causing the arginine (R) at amino acid position 170 to be replaced by a cysteine (C). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -