21-36387629-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_005441.3(CHAF1B):c.158A>G(p.Lys53Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,880 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CHAF1B NM_005441.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.55

Genes affected

CHAF1B (HGNC:1911): (chromatin assembly factor 1 subunit B) Chromatin assembly factor I (CAF-I) is required for the assembly of histone octamers onto newly-replicated DNA. CAF-I is composed of three protein subunits, p50, p60, and p150. The protein encoded by this gene corresponds to the p60 subunit and is required for chromatin assembly after replication. The encoded protein is differentially phosphorylated in a cell cycle-dependent manner. In addition, it is normally found in the nucleus except during mitosis, when it is released into the cytoplasm. This protein is a member of the WD-repeat HIR1 family and may also be involved in DNA repair. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.20611006).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CHAF1B	NM_005441.3	c.158A>G	p.Lys53Arg	missense_variant	3/14	ENST00000314103.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CHAF1B	ENST00000314103.6	c.158A>G	p.Lys53Arg	missense_variant	3/14	1	NM_005441.3	P1
CHAF1B	ENST00000480486.1	n.235A>G		non_coding_transcript_exon_variant	2/6	3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461880 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727238

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 31

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

Dec 08, 2023

The c.158A>G (p.K53R) alteration is located in exon 3 (coding exon 2) of the CHAF1B gene. This alteration results from a A to G substitution at nucleotide position 158, causing the lysine (K) at amino acid position 53 to be replaced by an arginine (R). 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	0.12
BayesDel_addAF	Benign	-0.053	T
BayesDel_noAF	Benign	-0.31
Cadd	Uncertain	24
Dann	Uncertain	1.0
DEOGEN2	Benign	0.062	T
Eigen	Benign	-0.12
Eigen_PC	Benign	0.084
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.87	D
M_CAP	Benign	0.027	D
MetaRNN	Benign	0.21	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.1	L
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.65	T
PROVEAN	Benign	-1.0	N
REVEL	Benign	0.11
Sift	Benign	0.13	T
Sift4G	Benign	0.24	T
Polyphen		0.019	B
Vest4		0.30
MutPred		0.39		Loss of ubiquitination at K53 (P = 0.0141);
MVP		0.62
MPC		0.63
ClinPred		0.91	D
GERP RS		4.7
Varity_R		0.13
gMVP		0.26

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr21-37759927;