6-31946239-C-T

Variant names:

• chr6-31946239-C-T
• rs771789056
• NM_001710.6:c.18C>T

Variant summary

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

The NM_001710.6(CFB):​c.18C>T​(p.Ser6Ser) 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 1,460,782 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: 6.8e-7 (0 hom.)
• Consequence: CFB NM_001710.6 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.529
• Publications: 0 publications found

Genes affected

CFB (HGNC:1037): (complement factor B) This gene encodes complement factor B, a component of the alternative pathway of complement activation. Factor B circulates in the blood as a single chain polypeptide. Upon activation of the alternative pathway, it is cleaved by complement factor D yielding the noncatalytic chain Ba and the catalytic subunit Bb. The active subunit Bb is a serine protease which associates with C3b to form the alternative pathway C3 convertase. Bb is involved in the proliferation of preactivated B lymphocytes, while Ba inhibits their proliferation. This gene localizes to the major histocompatibility complex (MHC) class III region on chromosome 6. This cluster includes several genes involved in regulation of the immune reaction. Polymorphisms in this gene are associated with a reduced risk of age-related macular degeneration. The polyadenylation site of this gene is 421 bp from the 5' end of the gene for complement component 2. [provided by RefSeq, Jul 2008]

CFB Gene-Disease associations (from GenCC):

• atypical hemolytic-uremic syndrome with B factor anomaly

  Inheritance: AD, Unknown Classification: STRONG, MODERATE, LIMITED Submitted by: Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae)
• complement factor b deficiency

  Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics
• C3 glomerulonephritis

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ENSG00000244255 (HGNC:):

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=-0.77).
• BP7: Synonymous conserved (PhyloP=-0.529 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001710.6. 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
	CFB	NM_001710.6	MANE Select	c.18C>T	p.Ser6Ser	synonymous	Exon 1 of 18	NP_001701.2	P00751-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CFB	ENST00000425368.7	TSL:1 MANE Select	c.18C>T	p.Ser6Ser	synonymous	Exon 1 of 18	ENSP00000416561.2	P00751-1
	ENSG00000244255	ENST00000456570.5	TSL:2	c.1571-134C>T		intron	N/A	ENSP00000410815.1	B4E1Z4
	CFB	ENST00000885733.1		c.18C>T	p.Ser6Ser	synonymous	Exon 1 of 18	ENSP00000555792.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000811 AC: 2 AN: 246556 AF XY: 0.0000149

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000109

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460782 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 726702

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52326

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112004

Other (OTH) AF: 0.00 AC: 0 AN: 60386

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.77
CADD	Benign	4.2
DANN	Benign	0.74
PhyloP100		-0.53
PromoterAI		-0.061	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.0

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs771789056; hg19: chr6-31914016;