6-27831308-T-C

Variant names:

• chr6-27831308-T-C
• NM_003541.3:c.220A>G

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_003541.3(H4C12):​c.220A>G​(p.Thr74Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000139 in 1,440,344 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: H4C12 NM_003541.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.22

Genes affected

H4C12 (HGNC:4784): (H4 clustered histone 12) 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 small histone gene cluster on chromosome 6p22-p21.3. [provided by RefSeq, Aug 2015]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a chain Histone H4 (size 101) in uniprot entity H4_HUMAN there are 11 pathogenic changes around while only 0 benign (100%) in NM_003541.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.761

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
H4C12	NM_003541.3	c.220A>G	p.Thr74Ala	missense_variant	Exon 1 of 1	ENST00000611927.2	NP_003532.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
H4C12	ENST00000611927.2	c.220A>G	p.Thr74Ala	missense_variant	Exon 1 of 1	6	NM_003541.3	ENSP00000479794.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000139 AC: 2 AN: 1440344 Hom.: 0 Cov.: 34 AF XY: 0.00000140 AC XY: 1 AN XY: 714316

Gnomad4 AFR exome AF: 0.00

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: 0.00000182

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Dec 03, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.220A>G (p.T74A) alteration is located in exon 1 (coding exon 1) of the HIST1H4K gene. This alteration results from a A to G substitution at nucleotide position 220, causing the threonine (T) at amino acid position 74 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
BayesDel_addAF	Pathogenic	0.23	D
BayesDel_noAF	Uncertain	0.090
CADD	Benign	23
DANN	Uncertain	1.0
Eigen	Uncertain	0.30
Eigen_PC	Uncertain	0.32
FATHMM_MKL	Uncertain	0.92	D
M_CAP	Uncertain	0.10	D
MetaRNN	Pathogenic	0.76	D
MetaSVM	Benign	-0.55	T
PrimateAI	Pathogenic	0.82	D
Sift4G	Benign	0.21	T
Vest4		0.81
MVP		0.048
ClinPred		0.99	D
GERP RS		4.3
gMVP		0.068

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: chr6-27799086; COSMIC: COSV100694829;