Genetic Variant H4C2:p.Asp86Tyr (chr6-26026997-C-A) – ACMG Classification: Likely_pathogenic (8 pts)

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1PM2PP3_Strong

The NM_003544.3(H4C2):c.256G>T(p.Asp86Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000062 in 1,614,064 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: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000062 ( 0 hom. )

Consequence

H4C2
NM_003544.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.55

Variant links:

Genes affected

H4C2 (HGNC:4789): (H4 clustered histone 2) 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]

H4C2 links:

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ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 8 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_003544.3

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.942

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
H4C2	NM_003544.3 link	c.256G>T	p.Asp86Tyr	missense_variant	Exon 1 of 1	ENST00000377745.5	NP_003535.1	P62805B2R4R0

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
H4C2	ENST00000377745.5 link	c.256G>T	p.Asp86Tyr	missense_variant	Exon 1 of 1	6	NM_003544.3	ENSP00000366974.2		P62805

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152224

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000159

AC:

AN:

251360

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135848

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000116

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000616

AC:

AN:

1461840

Hom.:

Cov.:

AF XY:

0.00000550

AC XY:

AN XY:

727228

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000134

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:

0.00000180

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152224

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74374

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Jan 24, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.256G>T (p.D86Y) alteration is located in exon 1 (coding exon 1) of the HIST1H4B gene. This alteration results from a G to T substitution at nucleotide position 256, causing the aspartic acid (D) at amino acid position 86 to be replaced by a tyrosine (Y). 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

0.25

BayesDel_noAF

Pathogenic

0.34

CADD

Pathogenic

DANN

Uncertain

0.99

Eigen

Uncertain

0.31

Eigen_PC

Uncertain

0.32

FATHMM_MKL

Pathogenic

0.98

M_CAP

Benign

0.054

MetaRNN

Pathogenic

0.94

MetaSVM

Uncertain

0.047

PrimateAI

Pathogenic

0.92

PROVEAN

Pathogenic

-7.9

Sift

Pathogenic

0.0

Sift4G

Pathogenic

0.0

Vest4

0.98

MVP

0.64

ClinPred

0.98

GERP RS

4.7

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

gMVP

0.82

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.36

Details are displayed if max score is > 0.2

DS_DG_spliceai

0.36

Position offset: 2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over