chrX-48791865-T-C

Variant names:

• chrX-48791865-T-C
• rs1557020166
• NM_002049.4:c.242T>C

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM1 BS2

The NM_002049.4(GATA1):​c.242T>C​(p.Leu81Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000364 in 1,097,948 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 2 hemizygotes in GnomAD. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 23)
  • Exomes 𝑓: 0.0000036 (0 hom. 2 hem.)
• Consequence: GATA1 NM_002049.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.91
• Publications: 0 publications found

Genes affected

GATA1 (HGNC:4170): (GATA binding protein 1) This gene encodes a protein which belongs to the GATA family of transcription factors. The protein plays an important role in erythroid development by regulating the switch of fetal hemoglobin to adult hemoglobin. Mutations in this gene have been associated with X-linked dyserythropoietic anemia and thrombocytopenia. [provided by RefSeq, Jul 2008]

GATA1 Gene-Disease associations (from GenCC):

• GATA1-Related X-Linked Cytopenia

  Inheritance: XL Classification: DEFINITIVE Submitted by: ClinGen
• thrombocytopenia, X-linked, with or without dyserythropoietic anemia

  Inheritance: XL Classification: STRONG, MODERATE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• beta-thalassemia-X-linked thrombocytopenia syndrome

  Inheritance: XL Classification: MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet
• Diamond-Blackfan anemia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• cutaneous porphyria

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• thrombocytopenia with congenital dyserythropoietic anemia

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• X-linked dyserythropoetic anemia with abnormal platelets and neutropenia

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000232828 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 8 uncertain in NM_002049.4
• BS2: High Hemizygotes in GnomAdExome4 at 2 AR,XL,AD gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GATA1	NM_002049.4	c.242T>C	p.Leu81Pro	missense_variant	Exon 3 of 6	ENST00000376670.9	NP_002040.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GATA1	ENST00000376670.9	c.242T>C	p.Leu81Pro	missense_variant	Exon 3 of 6	1	NM_002049.4	ENSP00000365858.3

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome AF: 0.00000364 AC: 4 AN: 1097948 Hom.: 0 Cov.: 32 AF XY: 0.00000550 AC XY: 2 AN XY: 363348

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 26398

American (AMR) AF: 0.00 AC: 0 AN: 35202

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 19380

East Asian (EAS) AF: 0.00 AC: 0 AN: 30205

South Asian (SAS) AF: 0.00 AC: 0 AN: 54149

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 40403

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4135

European-Non Finnish (NFE) AF: 0.00000475 AC: 4 AN: 841987

Other (OTH) AF: 0.00 AC: 0 AN: 46089

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 23

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Diamond-Blackfan anemia;C1845837:GATA binding protein 1 related thrombocytopenia with dyserythropoiesis Uncertain:1

Dec 17, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with GATA1-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces leucine with proline at codon 81 of the GATA1 protein (p.Leu81Pro). The leucine residue is moderately conserved and there is a moderate physicochemical difference between leucine and proline. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.42
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.23
CADD	Benign	22
DANN	Uncertain	0.98
DEOGEN2	Uncertain	0.46	T;T
FATHMM_MKL	Benign	0.62	D
LIST_S2	Benign	0.60	T;T
M_CAP	Uncertain	0.23	D
MetaRNN	Uncertain	0.47	T;T
MetaSVM	Uncertain	0.38	D
MutationAssessor	Benign	0.81	L;.
PhyloP100		2.9
PrimateAI	Uncertain	0.73	T
PROVEAN	Benign	-0.11	N;N
REVEL	Uncertain	0.64
Sift	Uncertain	0.0020	D;D
Sift4G	Uncertain	0.027	D;T
Polyphen		0.83	P;.
Vest4		0.51
MVP		0.90
MPC		0.18
ClinPred		0.37	T
GERP RS		4.1
Varity_R		0.20
gMVP		0.76
Mutation Taster		=88/12	polymorphism

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

Other links and lift over

dbSNP: rs1557020166; hg19: chrX-48650272;