17-44907384-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1 PM2

The NM_002055.5(GFAP):c.1262T>C(p.Ile421Thr) variant causes a missense change. The variant allele was found at a frequency of 0.00000658 in 152,088 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: GFAP NM_002055.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.75

Genes affected

GFAP (HGNC:4235): (glial fibrillary acidic protein) This gene encodes one of the major intermediate filament proteins of mature astrocytes. It is used as a marker to distinguish astrocytes from other glial cells during development. Mutations in this gene cause Alexander disease, a rare disorder of astrocytes in the central nervous system. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Oct 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_002055.5
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GFAP	NM_002055.5	c.1262T>C	p.Ile421Thr	missense_variant	9/9	ENST00000588735.3
GFAP	NM_001363846.2	c.1382T>C	p.Ile461Thr	missense_variant	10/10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GFAP	ENST00000588735.3	c.1262T>C	p.Ile421Thr	missense_variant	9/9	1	NM_002055.5	P1

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 152088 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00316

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 31

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 152088 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74304

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

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: 0.00000378

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

CeGaT Center for Human Genetics Tuebingen

Jan 01, 2017

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.88
BayesDel_addAF	Pathogenic	0.26	D
BayesDel_noAF	Uncertain	0.13
Cadd	Uncertain	23
Dann	Uncertain	0.98
DEOGEN2	Uncertain	0.60	D;.
Eigen	Benign	0.027
Eigen_PC	Benign	0.17
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Benign	0.68	T;T
M_CAP	Pathogenic	0.29	D
MetaRNN	Uncertain	0.74	D;D
MetaSVM	Pathogenic	0.82	D
MutationAssessor	Benign	1.6	L;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.72	T
Polyphen		0.0010	B;.
MutPred		0.42		Gain of phosphorylation at I421 (P = 0.0262);.;
MVP		1.0
ClinPred		0.85	D
GERP RS		4.8
Varity_R		0.36
gMVP		0.58

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

LitVar

Other links and lift over

dbSNP: rs1064797222; hg19: chr17-42984752;