5-132883346-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP2

The NM_014423.4(AFF4):c.3358C>G(p.Gln1120Glu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,460,010 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: AFF4 NM_014423.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.95

Genes affected

AFF4 (HGNC:17869): (ALF transcription elongation factor 4) The protein encoded by this gene belongs to the AF4 family of transcription factors involved in leukemia. It is a component of the positive transcription elongation factor b (P-TEFb) complex. A chromosomal translocation involving this gene and MLL gene on chromosome 11 is found in infant acute lymphoblastic leukemia with ins(5;11)(q31;q31q23). [provided by RefSeq, Oct 2011]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, AFF4

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
AFF4	NM_014423.4	c.3358C>G	p.Gln1120Glu	missense_variant	20/21	ENST00000265343.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AFF4	ENST00000265343.10	c.3358C>G	p.Gln1120Glu	missense_variant	20/21	1	NM_014423.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1460010 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 726286

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: 0.00000360

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Cognitive impairment - coarse facies - heart defects - obesity - pulmonary involvement - short stature - skeletal dysplasia syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Aug 08, 2023

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. This sequence change replaces glutamine, which is neutral and polar, with glutamic acid, which is acidic and polar, at codon 1120 of the AFF4 protein (p.Gln1120Glu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with AFF4-related conditions. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt AFF4 protein function. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Uncertain	-0.020
Cadd	Pathogenic	26
Dann	Uncertain	0.98
DEOGEN2	Benign	0.12	T
Eigen	Pathogenic	0.79
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.88	D
M_CAP	Benign	0.029	D
MetaRNN	Uncertain	0.60	D
MetaSVM	Benign	-0.39	T
MutationAssessor	Uncertain	2.4	M
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.79	T
PROVEAN	Benign	-0.56	N
REVEL	Benign	0.27
Sift	Uncertain	0.011	D
Sift4G	Uncertain	0.020	D
Polyphen		0.96	D
Vest4		0.59
MVP		0.75
MPC		2.3
ClinPred		0.94	D
GERP RS		5.9
Varity_R		0.60
gMVP		0.96

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: rs374222042; hg19: chr5-132219038;