chr7-2542142-C-A

Variant names:

• chr7-2542142-C-A
• rs76646873
• NM_152743.4:c.993G>T

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_152743.4(BRAT1):​c.993G>T​(p.Thr331Thr) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000141 in 1,413,538 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. T331T) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: BRAT1 NM_152743.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -3.67
• Publications: 0 publications found

Genes affected

BRAT1 (HGNC:21701): (BRCA1 associated ATM activator 1) The protein encoded by this ubiquitously expressed gene interacts with the tumor suppressing BRCA1 (breast cancer 1) protein and and the ATM (ataxia telangiectasia mutated) protein. ATM is thought to be a master controller of cell cycle checkpoint signalling pathways that are required for cellular responses to DNA damage such as double-strand breaks that are induced by ionizing radiation and complexes with BRCA1 in the multi-protein complex BASC (BRAC1-associated genome surveillance complex). The protein encoded by this gene is thought to play a role in the DNA damage pathway regulated by BRCA1 and ATM. [provided by RefSeq, Mar 2012]

BRAT1 Gene-Disease associations (from GenCC):

• neonatal-onset encephalopathy with rigidity and seizures

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, ClinGen, G2P, Labcorp Genetics (formerly Invitae)
• neurodevelopmental disorder with cerebellar atrophy and with or without seizures

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen, Ambry Genetics

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.77).
• BP7: Synonymous conserved (PhyloP=-3.67 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRAT1	NM_152743.4	c.993G>T	p.Thr331Thr	synonymous_variant	Exon 7 of 14	ENST00000340611.9	NP_689956.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRAT1	ENST00000340611.9	c.993G>T	p.Thr331Thr	synonymous_variant	Exon 7 of 14	1	NM_152743.4	ENSP00000339637.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000141 AC: 2 AN: 1413538 Hom.: 0 Cov.: 32 AF XY: 0.00000143 AC XY: 1 AN XY: 699180

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 32292

American (AMR) AF: 0.00 AC: 0 AN: 37430

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 24872

East Asian (EAS) AF: 0.0000267 AC: 1 AN: 37420

South Asian (SAS) AF: 0.00 AC: 0 AN: 80080

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 49472

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5638

European-Non Finnish (NFE) AF: 9.19e-7 AC: 1 AN: 1087876

Other (OTH) AF: 0.00 AC: 0 AN: 58458

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.77
CADD	Benign	0.016
DANN	Benign	0.39
PhyloP100		-3.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs76646873; hg19: chr7-2581776;