CFB p.Tyr135Tyr

Variant names:

• chr6-31947110-T-T
• ENST00000425368.7:c.

Your query was ambiguous. Multiple possible variants found:

• chr6-31947111--
• chr6-31947113-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The ENST00000425368.7(CFB):​c. variant causes a splice donor, intron change. The variant was absent in control chromosomes in GnomAD project. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 31)
• Consequence: CFB ENST00000425368.7 splice_donor, intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 5.55
• 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: Uncertain_significance. The variant received 4 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.081045754 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: ENST00000425368.7. 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
There are no transcript annotations for this variant.

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CFB	ENST00000425368.7	TSL:1 MANE Select	c.		splice_donor intron	N/A	ENSP00000416561.2	P00751-1
	ENSG00000244255	ENST00000456570.5	TSL:2	c.		splice_donor intron	N/A	ENSP00000410815.1	B4E1Z4
	ENSG00000244255	ENST00000477310.1	TSL:5	c.		splice_donor intron	N/A	ENSP00000418996.1	E7ETN3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		5.5

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr6-31914887;