17-44915261-G-C

Variant names:

• chr17-44915261-G-C
• rs57120761
• NM_002055.5:c.226C>G

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Strong

The NM_002055.5(GFAP):​c.226C>G​(p.Leu76Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as not provided (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L76P) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: GFAP NM_002055.5 missense
• Clinical Significance: not provided no classification provided O:2
• Conservation: PhyloP100: 8.15
• Publications: 5 publications found

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]

GFAP Gene-Disease associations (from GenCC):

• Alexander disease

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: ClinGen, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P
• Alexander disease type II

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PM1: In a hotspot region, there are 18 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 16 uncertain in NM_002055.5
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-44915260-A-G is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 3024231.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.985

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002055.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GFAP	NM_002055.5	MANE Select	c.226C>G	p.Leu76Val	missense	Exon 1 of 9	NP_002046.1
	GFAP	NM_001363846.2		c.226C>G	p.Leu76Val	missense	Exon 1 of 10	NP_001350775.1
	GFAP	NM_001242376.3		c.226C>G	p.Leu76Val	missense	Exon 1 of 7	NP_001229305.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GFAP	ENST00000588735.3	TSL:1 MANE Select	c.226C>G	p.Leu76Val	missense	Exon 1 of 9	ENSP00000466598.2
	GFAP	ENST00000591327.2	TSL:1	n.239C>G		non_coding_transcript_exon	Exon 1 of 5
	GFAP	ENST00000639277.1	TSL:5	c.226C>G	p.Leu76Val	missense	Exon 1 of 10	ENSP00000492432.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: not provided

Submissions summary: Other:2

Revision: no classification provided

Submissions by phenotype

not provided Other:1

Epithelial Biology; Institute of Medical Biology, Singapore

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

Alexander disease Other:1

GeneReviews

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.94
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.54
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.80
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D
M_CAP	Pathogenic	0.42	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.8	H
PhyloP100		8.1
PrimateAI	Pathogenic	0.81	D
PROVEAN	Uncertain	-2.6	D
REVEL	Pathogenic	0.93
Sift	Uncertain	0.0080	D
Sift4G	Uncertain	0.011	D
Polyphen		0.58	P
Vest4		0.86
MutPred		0.97		Gain of MoRF binding (P = 0.1006)
MVP		1.0
MPC		1.1
ClinPred		0.99	D
GERP RS		4.8
PromoterAI		0.0066	Neutral
Varity_R		0.93
gMVP		0.98
Mutation Taster		=2/98	disease causing (ClinVar)

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: rs57120761; hg19: chr17-42992629;