6-26104083-C-A

Variant names:

• chr6-26104083-C-A
• NM_003542.4:c.136C>A

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1 PM2 PP3_Strong PP5_Moderate

The NM_003542.4(H4C3):​c.136C>A​(p.Arg46Ser) 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 Likely pathogenic (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: H4C3 NM_003542.4 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 6.00

Genes affected

H4C3 (HGNC:4787): (H4 clustered histone 3) Histones are basic nuclear proteins that are responsible for the nucleosome structure of the chromosomal fiber in eukaryotes. Two molecules of each of the four core histones (H2A, H2B, H3, and H4) form an octamer, around which approximately 146 bp of DNA is wrapped in repeating units, called nucleosomes. The linker histone, H1, interacts with linker DNA between nucleosomes and functions in the compaction of chromatin into higher order structures. This gene is intronless and encodes a replication-dependent histone that is a member of the histone H4 family. Transcripts from this gene lack polyA tails but instead contain a palindromic termination element. This gene is found in the large histone gene cluster on chromosome 6. [provided by RefSeq, Aug 2015]

H2BC4 (HGNC:4757): (H2B clustered histone 4) Histones are basic nuclear proteins that are responsible for the nucleosome structure of the chromosomal fiber in eukaryotes. Two molecules of each of the four core histones (H2A, H2B, H3, and H4) form an octamer, around which approximately 146 bp of DNA is wrapped in repeating units, called nucleosomes. The linker histone, H1, interacts with linker DNA between nucleosomes and functions in the compaction of chromatin into higher order structures. The protein has antibacterial and antifungal antimicrobial activity. The main transcript variant of this gene is intronless and encodes a replication-dependent histone that is a member of the histone H2B family. This transcript variant lacks a polyA tail but instead contains a palindromic termination element. This gene is found in the large histone gene cluster on chromosome 6. [provided by RefSeq, Apr 2020]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PM1: In a chain Histone H4 (size 101) in uniprot entity H4_HUMAN there are 23 pathogenic changes around while only 0 benign (100%) in NM_003542.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.947
• PP5: Variant 6-26104083-C-A is Pathogenic according to our data. Variant chr6-26104083-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2597503.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
H4C3	NM_003542.4	c.136C>A	p.Arg46Ser	missense_variant	Exon 1 of 1	ENST00000377803.4	NP_003533.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
H4C3	ENST00000377803.4	c.136C>A	p.Arg46Ser	missense_variant	Exon 1 of 1	6	NM_003542.4	ENSP00000367034.3
H2BC4	ENST00000707188.1	n.*10-13049G>T		intron_variant	Intron 1 of 2			ENSP00000516775.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Pathogenic:1

Sep 11, 2023

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.136C>A (p.R46S) alteration is located in exon 1 (coding exon 1) of the HIST1H4C gene. This alteration results from a C to A substitution at nucleotide position 136, causing the arginine (R) at amino acid position 46 to be replaced by a serine (S). This variant was not reported in population-based cohorts in the Genome Aggregation Database (gnomAD). A different alteration at the same codon in a paralogous gene, H4C5 c.136C>T (p.R46C), has been reported de novo in multiple individuals with features consistent with H4C5-related Tessadori-van Haaften neurodevelopmental syndrome (Tessadori, 2022). This amino acid position is highly conserved in available vertebrate species. Based on internal structural analysis, this variant interferes with the hydrogen bond linking H3 and H4 (Davey, 2002; Tessadori, 2022). This alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, this alteration is classified as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.32
CADD	Uncertain	25
DANN	Uncertain	1.0
Eigen	Uncertain	0.27
Eigen_PC	Uncertain	0.28
FATHMM_MKL	Uncertain	0.95	D
M_CAP	Uncertain	0.22	D
MetaRNN	Pathogenic	0.95	D
MetaSVM	Uncertain	0.029	D
PrimateAI	Pathogenic	0.93	D
PROVEAN	Pathogenic	-5.9	D
REVEL	Pathogenic	0.81
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.0030	D
Vest4		0.95
MutPred		0.79		Loss of MoRF binding (P = 0.0381);
MVP		0.45
ClinPred		1.0	D
GERP RS		4.6
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		2.6
gMVP		0.35

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr6-26104311;