chrX-148885517-C-T

Variant names:

• chrX-148885517-C-T
• rs758440
• NM_002025.4:c.1263-372C>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_002025.4(AFF2):​c.1263-372C>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 22)
• Consequence: AFF2 NM_002025.4 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.297
• Publications: 1 publications found

Genes affected

AFF2 (HGNC:3776): (ALF transcription elongation factor 2) This gene encodes a putative transcriptional activator that is a member of the AF4\FMR2 gene family. This gene is associated with the folate-sensitive fragile X E locus on chromosome X. A repeat polymorphism in the fragile X E locus results in silencing of this gene causing Fragile X E syndrome. Fragile X E syndrome is a form of nonsyndromic X-linked cognitive disability. In addition, this gene contains 6-25 GCC repeats that are expanded to >200 repeats in the disease state. Alternate splicing results in multiple transcript variants.[provided by RefSeq, Jul 2016]

AFF2 Gene-Disease associations (from GenCC):

• FRAXE intellectual disability

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), G2P
• non-syndromic X-linked intellectual disability

  Inheritance: XL Classification: DEFINITIVE Submitted by: ClinGen

ACMG classification

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

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.81).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002025.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	AFF2	NM_002025.4	MANE Select	c.1263-372C>T		intron	N/A	NP_002016.2	P51816-1
	AFF2	NM_001169123.2		c.1233-372C>T		intron	N/A	NP_001162594.1	P51816-5
	AFF2	NM_001169122.2		c.1164-372C>T		intron	N/A	NP_001162593.1	P51816-3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	AFF2	ENST00000370460.7	TSL:5 MANE Select	c.1263-372C>T		intron	N/A	ENSP00000359489.2	P51816-1
	AFF2	ENST00000342251.7	TSL:1	c.1164-372C>T		intron	N/A	ENSP00000345459.4	P51816-3
	AFF2	ENST00000370457.9	TSL:1	c.1158-372C>T		intron	N/A	ENSP00000359486.6	P51816-6

Frequencies

GnomAD3 genomes Cov.: 22

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 22

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.81
CADD	Benign	9.7
DANN	Benign	0.73
PhyloP100		0.30

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: rs758440; hg19: chrX-147967047;