5-151856338-G-T

Variant names:

• chr5-151856338-G-T
• rs114046477
• NM_000171.4:c.522C>A

Variant summary

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

The NM_000171.4(GLRA1):​c.522C>A​(p.Pro174Pro) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,459,964 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. P174P) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: GLRA1 NM_000171.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.665
• Publications: 0 publications found

Genes affected

GLRA1 (HGNC:4326): (glycine receptor alpha 1) The protein encoded by this gene is a subunit of a pentameric inhibitory glycine receptor, which mediates postsynaptic inhibition in the central nervous system. Defects in this gene are a cause of startle disease (STHE), also known as hereditary hyperekplexia or congenital stiff-person syndrome. Multiple transcript variants encoding different isoforms have been found. [provided by RefSeq, Dec 2015]

GLRA1 Gene-Disease associations (from GenCC):

• hyperekplexia 1

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• hereditary hyperekplexia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

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=-0.53).
• BP7: Synonymous conserved (PhyloP=0.665 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GLRA1	NM_000171.4	c.522C>A	p.Pro174Pro	synonymous_variant	Exon 5 of 9	ENST00000274576.9	NP_000162.2
GLRA1	NM_001146040.2	c.522C>A	p.Pro174Pro	synonymous_variant	Exon 5 of 9		NP_001139512.1
GLRA1	NM_001292000.2	c.273C>A	p.Pro91Pro	synonymous_variant	Exon 4 of 8		NP_001278929.1
GLRA1	XM_047417105.1	c.570C>A	p.Pro190Pro	synonymous_variant	Exon 5 of 9		XP_047273061.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GLRA1	ENST00000274576.9	c.522C>A	p.Pro174Pro	synonymous_variant	Exon 5 of 9	1	NM_000171.4	ENSP00000274576.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1459964 Hom.: 0 Cov.: 29 AF XY: 0.00000138 AC XY: 1 AN XY: 726356

⚠️ 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: 33436

American (AMR) AF: 0.00 AC: 0 AN: 44690

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26088

East Asian (EAS) AF: 0.00 AC: 0 AN: 39650

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86186

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53264

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1110624

Other (OTH) AF: 0.00 AC: 0 AN: 60258

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.53
CADD	Benign	7.7
DANN	Benign	0.61
PhyloP100		0.67

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: rs114046477; hg19: chr5-151235899;