chr9-109137476-G-A

Variant names:

• chr9-109137476-G-A
• rs570300260
• NM_014334.4:c.861C>T

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 2P and 3B. PM2 BP4_Moderate BP7

The NM_014334.4(FRRS1L):​c.861C>T​(p.Tyr287Tyr) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000686 in 1,458,040 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.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: FRRS1L NM_014334.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 2.13
• Publications: 0 publications found

Genes affected

FRRS1L (HGNC:1362): (ferric chelate reductase 1 like) This gene encodes a component of the outer-core of an alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor protein in the brain. The encoded protein is thought to interact with inner-core components of the receptor, and play a role in the modulation of glutamate signaling. Mutations in this gene are associated with early infantile epileptic encephalopathy 37. [provided by RefSeq, Jul 2016]

FRRS1L Gene-Disease associations (from GenCC):

• developmental and epileptic encephalopathy, 37

  Inheritance: AR Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• autosomal recessive non-syndromic intellectual disability

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.45).
• BP7: Synonymous conserved (PhyloP=2.13 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FRRS1L	NM_014334.4	c.861C>T	p.Tyr287Tyr	synonymous_variant	Exon 5 of 5	ENST00000561981.5	NP_055149.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FRRS1L	ENST00000561981.5	c.861C>T	p.Tyr287Tyr	synonymous_variant	Exon 5 of 5	1	NM_014334.4	ENSP00000477141.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000399 AC: 1 AN: 250824 AF XY: 0.00000738

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.86e-7 AC: 1 AN: 1458040 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 725276

⚠️ 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: 33426

American (AMR) AF: 0.00 AC: 0 AN: 44540

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26026

East Asian (EAS) AF: 0.00 AC: 0 AN: 39672

South Asian (SAS) AF: 0.0000117 AC: 1 AN: 85592

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53240

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5758

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1109584

Other (OTH) AF: 0.00 AC: 0 AN: 60202

⚠️ 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

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.45
CADD	Benign	8.7
DANN	Benign	0.60
PhyloP100		2.1

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs570300260; hg19: chr9-111899756;