chr5-141344220-G-C

Position:

• chr5-141344220-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_018916.4(PCDHGA3):​c.187G>C​(p.Gly63Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000144 in 1,461,710 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.000014 (0 hom.)
• Consequence: PCDHGA3 NM_018916.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.448

Genes affected

PCDHGA3 (HGNC:8701): (protocadherin gamma subfamily A, 3) This gene is a member of the protocadherin gamma gene cluster, one of three related clusters tandemly linked on chromosome five. These gene clusters have an immunoglobulin-like organization, suggesting that a novel mechanism may be involved in their regulation and expression. The gamma gene cluster includes 22 genes divided into 3 subfamilies. Subfamily A contains 12 genes, subfamily B contains 7 genes and 2 pseudogenes, and the more distantly related subfamily C contains 3 genes. The tandem array of 22 large, variable region exons are followed by a constant region, containing 3 exons shared by all genes in the cluster. Each variable region exon encodes the extracellular region, which includes 6 cadherin ectodomains and a transmembrane region. The constant region exons encode the common cytoplasmic region. These neural cadherin-like cell adhesion proteins most likely play a critical role in the establishment and function of specific cell-cell connections in the brain. Alternative splicing has been described for the gamma cluster genes. [provided by RefSeq, Jul 2008]

PCDHGA1 (HGNC:8696): (protocadherin gamma subfamily A, 1) This gene is a member of the protocadherin gamma gene cluster, one of three related clusters tandemly linked on chromosome five. These gene clusters have an immunoglobulin-like organization, suggesting that a novel mechanism may be involved in their regulation and expression. The gamma gene cluster includes 22 genes divided into 3 subfamilies. Subfamily A contains 12 genes, subfamily B contains 7 genes and 2 pseudogenes, and the more distantly related subfamily C contains 3 genes. The tandem array of 22 large, variable region exons are followed by a constant region, containing 3 exons shared by all genes in the cluster. Each variable region exon encodes the extracellular region, which includes 6 cadherin ectodomains and a transmembrane region. The constant region exons encode the common cytoplasmic region. These neural cadherin-like cell adhesion proteins most likely play a critical role in the establishment and function of specific cell-cell connections in the brain. Alternative splicing has been described for the gamma cluster genes. [provided by RefSeq, Jul 2008]

PCDHGA2 (HGNC:8700): (protocadherin gamma subfamily A, 2) This gene is a member of the protocadherin gamma gene cluster, one of three related clusters tandemly linked on chromosome five. These gene clusters have an immunoglobulin-like organization, suggesting that a novel mechanism may be involved in their regulation and expression. The gamma gene cluster includes 22 genes divided into 3 subfamilies. Subfamily A contains 12 genes, subfamily B contains 7 genes and 2 pseudogenes, and the more distantly related subfamily C contains 3 genes. The tandem array of 22 large, variable region exons are followed by a constant region, containing 3 exons shared by all genes in the cluster. Each variable region exon encodes the extracellular region, which includes 6 cadherin ectodomains and a transmembrane region. The constant region exons encode the common cytoplasmic region. These neural cadherin-like cell adhesion proteins most likely play a critical role in the establishment and function of specific cell-cell connections in the brain. Alternative splicing has been described for the gamma cluster genes. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.14764437).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PCDHGA3	NM_018916.4	c.187G>C	p.Gly63Arg	missense_variant	1/4	ENST00000253812.8	NP_061739.2
PCDHGA1	NM_018912.3	c.2421+11115G>C		intron_variant		ENST00000517417.3	NP_061735.1
PCDHGA2	NM_018915.4	c.2424+2825G>C		intron_variant		ENST00000394576.3	NP_061738.1
PCDHGA3	NM_032011.2	c.187G>C	p.Gly63Arg	missense_variant	1/1		NP_114400.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PCDHGA3	ENST00000253812.8	c.187G>C	p.Gly63Arg	missense_variant	1/4	1	NM_018916.4	ENSP00000253812	P1
PCDHGA2	ENST00000394576.3	c.2424+2825G>C		intron_variant		1	NM_018915.4	ENSP00000378077	P1
PCDHGA1	ENST00000517417.3	c.2421+11115G>C		intron_variant		1	NM_018912.3	ENSP00000431083	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.0000144 AC: 21 AN: 1461710 Hom.: 0 Cov.: 31 AF XY: 0.0000179 AC XY: 13 AN XY: 727144

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000171

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000756

ExAC AF: 0.00000825 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 01, 2021

The c.187G>C (p.G63R) alteration is located in exon 1 (coding exon 1) of the PCDHGA3 gene. This alteration results from a G to C substitution at nucleotide position 187, causing the glycine (G) at amino acid position 63 to be replaced by an arginine (R). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Benign	-0.25	T
BayesDel_noAF	Benign	-0.60
CADD	Benign	17
DANN	Benign	0.73
DEOGEN2	Benign	0.026	.;T
Eigen	Benign	-0.72
Eigen_PC	Benign	-0.68
FATHMM_MKL	Benign	0.19	N
LIST_S2	Benign	0.78	T;T
M_CAP	Benign	0.011	T
MetaRNN	Benign	0.15	T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.1	L;L
MutationTaster	Benign	0.84	D;D;N
PROVEAN	Pathogenic	-5.9	.;D
REVEL	Benign	0.060
Sift	Benign	0.50	.;T
Sift4G	Benign	0.66	T;T
Polyphen		0.30	B;B
Vest4		0.28
MutPred		0.61		Loss of methylation at R62 (P = 0.0478);Loss of methylation at R62 (P = 0.0478);
MVP		0.34
MPC		1.1
ClinPred		0.73	D
GERP RS		1.7
Varity_R		0.19
gMVP		0.59

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

Publications

LitVar

Other links and lift over

dbSNP: rs761098701; hg19: chr5-140723787;