6-26240496-G-A

Variant names:

• chr6-26240496-G-A
• rs1201414781
• NM_003540.4:c.71G>A

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1 PM2

The NM_003540.4(H4C6):​c.71G>A​(p.Arg24His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,457,752 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: H4C6 NM_003540.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.57

Genes affected

H4C6 (HGNC:4783): (H4 clustered histone 6) 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]

ENSG00000291336 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM1: In a chain Histone H4 (size 101) in uniprot entity H4_HUMAN there are 12 pathogenic changes around while only 0 benign (100%) in NM_003540.4
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
H4C6	NM_003540.4	c.71G>A	p.Arg24His	missense_variant	Exon 1 of 1	ENST00000244537.6	NP_003531.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
H4C6	ENST00000244537.6	c.71G>A	p.Arg24His	missense_variant	Exon 1 of 1	6	NM_003540.4	ENSP00000244537.6
ENSG00000291336	ENST00000707189.1	n.999+116325G>A		intron_variant	Intron 1 of 1
ENSG00000291338	ENST00000707191.1	n.1000+82375G>A		intron_variant	Intron 1 of 1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1457752 Hom.: 0 Cov.: 32 AF XY: 0.00000276 AC XY: 2 AN XY: 724432

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000253

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.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Jan 10, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.71G>A (p.R24H) alteration is located in exon 1 (coding exon 1) of the HIST1H4F gene. This alteration results from a G to A substitution at nucleotide position 71, causing the arginine (R) at amino acid position 24 to be replaced by a histidine (H). 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
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.36
CADD	Uncertain	24
DANN	Uncertain	1.0
Eigen	Uncertain	0.37
Eigen_PC	Uncertain	0.38
FATHMM_MKL	Benign	0.38	N
M_CAP	Benign	0.042	D
MetaRNN	Uncertain	0.70	D
MetaSVM	Benign	-0.32	T
PrimateAI	Pathogenic	0.90	D
Sift4G	Uncertain	0.031	D
Vest4		0.83
MutPred		0.35		Gain of catalytic residue at D25 (P = 0.0652);
MVP		0.067
ClinPred		1.0	D
GERP RS		4.7
gMVP		0.15

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: rs1201414781; hg19: chr6-26240724;