5-141340187-A-C

Position:

• chr5-141340187-A-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The ENST00000394576.3(PCDHGA2):​c.1216A>C​(p.Thr406Pro) variant causes a missense change. The variant allele was found at a frequency of 0.00000657 in 152,230 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: PCDHGA2 ENST00000394576.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.81

Genes affected

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]

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.955

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
PCDHGA2	NM_018915.4	c.1216A>C	p.Thr406Pro	missense_variant	1/4	ENST00000394576.3	NP_061738.1
PCDHGA1	NM_018912.3	c.2421+7082A>C		intron_variant		ENST00000517417.3	NP_061735.1
PCDHGA2	NM_032009.3	c.1216A>C	p.Thr406Pro	missense_variant	1/1		NP_114398.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
PCDHGA2	ENST00000394576.3	c.1216A>C	p.Thr406Pro	missense_variant	1/4	1	NM_018915.4	ENSP00000378077	P1
PCDHGA1	ENST00000517417.3	c.2421+7082A>C		intron_variant		1	NM_018912.3	ENSP00000431083	P1
PCDHGA2	ENST00000528330.2	c.1216A>C	p.Thr406Pro	missense_variant	1/1			ENSP00000483020

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152230 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 34

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152230 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74374

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

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 20, 2023

The c.1216A>C (p.T406P) alteration is located in exon 1 (coding exon 1) of the PCDHGA2 gene. This alteration results from a A to C substitution at nucleotide position 1216, causing the threonine (T) at amino acid position 406 to be replaced by a proline (P). 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	Pathogenic	0.57
BayesDel_addAF	Pathogenic	0.20	D
BayesDel_noAF	Uncertain	0.050
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Benign	0.080	.;T
Eigen	Pathogenic	0.76
Eigen_PC	Uncertain	0.59
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.94	D;D
M_CAP	Benign	0.077	D
MetaRNN	Pathogenic	0.96	D;D
MetaSVM	Uncertain	-0.0061	T
MutationAssessor	Pathogenic	3.5	M;M
MutationTaster	Benign	1.0	D;N
PROVEAN	Pathogenic	-5.8	.;D
REVEL	Uncertain	0.50
Sift	Pathogenic	0.0	.;D
Sift4G	Pathogenic	0.0010	D;D
Polyphen		1.0	D;D
Vest4		0.72
MutPred		0.80		Loss of phosphorylation at T406 (P = 0.0634);Loss of phosphorylation at T406 (P = 0.0634);
MVP		0.88
MPC		1.2
ClinPred		0.99	D
GERP RS		4.9
Varity_R		0.91
gMVP		0.52

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: rs1756914771; hg19: chr5-140719754;