7-117711683-G-C

Variant summary

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

The NM_033427.3(CTTNBP2):c.4846C>G(p.Pro1616Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,722 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P1616S) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CTTNBP2 NM_033427.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.27

Genes affected

CTTNBP2 (HGNC:15679): (cortactin binding protein 2) This gene encodes a protein with six ankyrin repeats and several proline-rich regions. A similar gene in rat interacts with a central regulator of the actin cytoskeleton. [provided by RefSeq, Jul 2008]

CFTR (HGNC:1884): (CF transmembrane conductance regulator) This gene encodes a member of the ATP-binding cassette (ABC) transporter superfamily. The encoded protein functions as a chloride channel, making it unique among members of this protein family, and controls ion and water secretion and absorption in epithelial tissues. Channel activation is mediated by cycles of regulatory domain phosphorylation, ATP-binding by the nucleotide-binding domains, and ATP hydrolysis. Mutations in this gene cause cystic fibrosis, the most common lethal genetic disorder in populations of Northern European descent. The most frequently occurring mutation in cystic fibrosis, DeltaF508, results in impaired folding and trafficking of the encoded protein. Multiple pseudogenes have been identified in the human genome. [provided by RefSeq, Aug 2017]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CTTNBP2	NM_033427.3	c.4846C>G	p.Pro1616Ala	missense_variant	23/23	ENST00000160373.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CTTNBP2	ENST00000160373.8	c.4846C>G	p.Pro1616Ala	missense_variant	23/23	1	NM_033427.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461722 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727162

Gnomad4 AFR exome AF: 0.0000299

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

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

Mar 07, 2024

The c.4846C>G (p.P1616A) alteration is located in exon 23 (coding exon 23) of the CTTNBP2 gene. This alteration results from a C to G substitution at nucleotide position 4846, causing the proline (P) at amino acid position 1616 to be replaced by an alanine (A). 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	0.20
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Uncertain	0.0
Cadd	Uncertain	25
Dann	Uncertain	1.0
DEOGEN2	Benign	0.047	T
Eigen	Uncertain	0.62
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.92	D
M_CAP	Benign	0.078	D
MetaRNN	Uncertain	0.55	D
MetaSVM	Uncertain	0.035	D
MutationAssessor	Uncertain	2.3	M
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.57	T
PROVEAN	Benign	-1.9	N
REVEL	Uncertain	0.40
Sift	Benign	0.062	T
Sift4G	Uncertain	0.014	D
Polyphen		1.0	D
Vest4		0.50
MutPred		0.35		Gain of MoRF binding (P = 0.1286);
MVP		0.82
MPC		0.48
ClinPred		0.75	D
GERP RS		5.9
Varity_R		0.076
gMVP		0.19

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: rs762215104; hg19: chr7-117351737;