rs1644662055

Variant names:

• chr1-56929408-G-A
• rs1644662055
• NM_000066.4:c.1772C>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_000066.4(C8B):​c.1772C>T​(p.Ser591Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,192 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
• Consequence: C8B NM_000066.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.526
• Publications: 0 publications found

Genes affected

C8B (HGNC:1353): (complement C8 beta chain) This gene encodes one of the three subunits of the complement component 8 (C8) protein. C8 is composed of equimolar amounts of alpha, beta and gamma subunits, which are encoded by three separate genes. C8 is one component of the membrane attack complex, which mediates cell lysis, and it initiates membrane penetration of the complex. This protein mediates the interaction of C8 with the C5b-7 membrane attack complex precursor. In humans deficiency of this protein is associated with increased risk of meningococcal infections. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jun 2013]

C8B Gene-Disease associations (from GenCC):

• type II complement component 8 deficiency

  Inheritance: AR Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.060136795).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000066.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	C8B	NM_000066.4	MANE Select	c.1772C>T	p.Ser591Phe	missense	Exon 12 of 12	NP_000057.3	P07358
	C8B	NM_001278543.2		c.1616C>T	p.Ser539Phe	missense	Exon 13 of 13	NP_001265472.2
	C8B	NM_001278544.2		c.1586C>T	p.Ser529Phe	missense	Exon 13 of 13	NP_001265473.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	C8B	ENST00000371237.9	TSL:1 MANE Select	c.1772C>T	p.Ser591Phe	missense	Exon 12 of 12	ENSP00000360281.4	P07358
	C8B	ENST00000696164.1		c.1772C>T	p.Ser591Phe	missense	Exon 13 of 13	ENSP00000512454.1	A0A8Q3WL56
	C8B	ENST00000875298.1		c.1772C>T	p.Ser591Phe	missense	Exon 13 of 13	ENSP00000545357.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152192 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

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.: 33

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152192 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74344

African (AFR) AF: 0.00 AC: 0 AN: 41444

American (AMR) AF: 0.0000655 AC: 1 AN: 15272

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5198

South Asian (SAS) AF: 0.00 AC: 0 AN: 4834

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10616

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68036

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.17
BayesDel_addAF	Benign	-0.28	T
BayesDel_noAF	Benign	-0.64
CADD	Benign	11
DANN	Benign	0.85
DEOGEN2	Benign	0.010	T
Eigen	Benign	-1.4
Eigen_PC	Benign	-1.5
FATHMM_MKL	Benign	0.0018	N
LIST_S2	Benign	0.74	T
M_CAP	Benign	0.0038	T
MetaRNN	Benign	0.060	T
MetaSVM	Benign	-0.99	T
PhyloP100		-0.53
PrimateAI	Benign	0.36	T
PROVEAN	Benign	0.060	N
REVEL	Benign	0.019
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		0.0	B
Vest4		0.17
MutPred		0.37		Loss of phosphorylation at S591 (P = 0.0266)
MVP		0.17
MPC		0.25
ClinPred		0.15	T
GERP RS		-5.2
gMVP		0.52
Mutation Taster		=89/11	polymorphism

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: rs1644662055; hg19: chr1-57395081;