rs398124146

chr16-3738617-G-Achr16-3738617-G-Cchr16-3738617-G-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM1 PM2 PM5 PP2 PP3_Strong PP5

The NM_004380.3(CREBBP):c.4336C>T(p.Arg1446Cys) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1446G) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CREBBP NM_004380.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:13 U:1
• Conservation: PhyloP100: 4.23

Genes affected

CREBBP (HGNC:2348): (CREB binding protein) This gene is ubiquitously expressed and is involved in the transcriptional coactivation of many different transcription factors. First isolated as a nuclear protein that binds to cAMP-response element binding protein (CREB), this gene is now known to play critical roles in embryonic development, growth control, and homeostasis by coupling chromatin remodeling to transcription factor recognition. The protein encoded by this gene has intrinsic histone acetyltransferase activity and also acts as a scaffold to stabilize additional protein interactions with the transcription complex. This protein acetylates both histone and non-histone proteins. This protein shares regions of very high sequence similarity with protein p300 in its bromodomain, cysteine-histidine-rich regions, and histone acetyltransferase domain. Mutations in this gene cause Rubinstein-Taybi syndrome (RTS). Chromosomal translocations involving this gene have been associated with acute myeloid leukemia. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Feb 2009]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_004380.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr16-3738617-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 376388.Status of the report is no_assertion_criteria_provided, 0 stars.
• PP2: Missense variant where missense usually causes diseases, CREBBP
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.982
• PP5: Variant 16-3738617-G-A is Pathogenic according to our data. Variant chr16-3738617-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 95047.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=1, Pathogenic=1}. Variant chr16-3738617-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CREBBP	NM_004380.3	c.4336C>T	p.Arg1446Cys	missense_variant	26/31	ENST00000262367.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CREBBP	ENST00000262367.10	c.4336C>T	p.Arg1446Cys	missense_variant	26/31	1	NM_004380.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:13 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Glioblastoma Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

Database of Curated Mutations (DoCM)

May 31, 2016

- -

Gastric adenocarcinoma Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

Database of Curated Mutations (DoCM)

May 31, 2016

- -

Squamous cell lung carcinoma Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

Database of Curated Mutations (DoCM)

May 31, 2016

- -

Medulloblastoma Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

Database of Curated Mutations (DoCM)

May 31, 2016

- -

Malignant melanoma of skin Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

Database of Curated Mutations (DoCM)

May 31, 2016

- -

Rubinstein-Taybi syndrome Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Invitae

Apr 24, 2018

This sequence change replaces arginine with cysteine at codon 1446 of the CREBBP protein (p.Arg1446Cys). The arginine residue is highly conserved and there is a large physicochemical difference between arginine and cysteine. This variant is not present in population databases (ExAC no frequency). This variant has been reported to be de novo in an individual affected with polysyndactyly, hirsutism, and clitoromegaly (Invitae). ClinVar contains an entry for this variant (Variation ID: 95047). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Transitional cell carcinoma of the bladder Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

Database of Curated Mutations (DoCM)

May 31, 2016

- -

Neoplasm of uterine cervix Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

Database of Curated Mutations (DoCM)

May 31, 2016

- -

Rubinstein-Taybi syndrome due to CREBBP mutations Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

May 20, 2021

Variant summary: CREBBP c.4336C>T (p.Arg1446Cys) results in a non-conservative amino acid change located in the CBP/p300-type histone acetyltransferase domain (IPR031162) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 251384 control chromosomes (gnomAD). c.4336C>T has been reported in the literature as a somatic mutation in multiple individuals affected with a variety of tumor phenotypes. These reports do not provide unequivocal conclusions about association of the variant with Rubinstein-Taybi Syndrome. However, this variant was previously observed at our laboratory as a de-novo variant in a fetal exome case presenting with increased NT, IUGR, polydactyly, small cerebellum and cardiac anamolies. In addition, one other ClinVar submitter (evaluation after 2014) classified the variant as Likely Pathogenic, citing a de-novo occurrence observed in a sample submitted to their laboratory. These findings suggest a de-novo etiology for disease. At least one publication reports in-vitro experimental evidence showing that the R1446C variant confers a loss-of-function as indicated by reduced acetyltransferase activity in bladder cancer and HEK293 cell lines (e.g. Duex_2018). Based on the evidence outlined above, the variant was classified as pathogenic. -

Adenoid cystic carcinoma Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

Database of Curated Mutations (DoCM)

May 31, 2016

- -

Neoplasm of the large intestine Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

Database of Curated Mutations (DoCM)

May 31, 2016

- -

Hepatocellular carcinoma Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

Database of Curated Mutations (DoCM)

May 31, 2016

- -

Squamous cell carcinoma of the head and neck Pathogenic:1

Likely pathogenic, no assertion criteria provided

literature only

Database of Curated Mutations (DoCM)

May 31, 2016

- -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Eurofins Ntd Llc (ga)

Jun 11, 2013

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.48
Cadd	Pathogenic	28
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D;.;.
Eigen	Pathogenic	0.79
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Pathogenic	1.0	D;D;D
M_CAP	Pathogenic	0.82	D
MetaRNN	Pathogenic	0.98	D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.4	M;.;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.92	D
PROVEAN	Pathogenic	-7.6	D;D;.
REVEL	Pathogenic	0.95
Sift	Uncertain	0.0070	D;D;.
Sift4G	Pathogenic	0.0	D;D;.
Polyphen		1.0	D;.;.
Vest4		0.92
MutPred		0.89		Gain of sheet (P = 0.0344);.;.;
MVP		0.98
MPC		1.5
ClinPred		1.0	D
GERP RS		4.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.61
gMVP		0.98

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: rs398124146; hg19: chr16-3788618; COSMIC: COSV52113365; COSMIC: COSV52113365;