chr17-44903550-C-T

Position:

• chr17-44903550-C-T

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 0P and 8B. BP4_Strong BS2

The NM_001258400.2(FAM187A):​c.-280C>T variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000244 in 1,359,636 control chromosomes in the GnomAD database, including 4 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00025 (3 hom., cov: 32)
  • Exomes 𝑓: 0.00024 (1 hom.)
• Consequence: FAM187A NM_001258400.2 5_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.398

Genes affected

FAM187A (HGNC:35153): (family with sequence similarity 187 member A) Predicted to be integral component of membrane. [provided by Alliance of Genome Resources, Apr 2022]

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]

CCDC103 (HGNC:32700): (coiled-coil domain containing 103) Enables protein homodimerization activity. Involved in axonemal dynein complex assembly; cilium movement; and determination of left/right symmetry. Predicted to be located in axoneme. Predicted to be part of outer dynein arm. Implicated in primary ciliary dyskinesia 17. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Benign. Variant got -8 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.87).
• BS2: High Homozygotes in GnomAd4 at 3 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FAM187A	NM_001258400.2	c.-280C>T		5_prime_UTR_variant	1/1	ENST00000331733.5
GFAP	NM_002055.5	c.*3797G>A		3_prime_UTR_variant	9/9	ENST00000588735.3
CCDC103	NM_213607.3	c.*733C>T		3_prime_UTR_variant	4/4	ENST00000417826.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FAM187A	ENST00000331733.5	c.-280C>T		5_prime_UTR_variant	1/1	1	NM_001258400.2	P1
CCDC103	ENST00000417826.3	c.*733C>T		3_prime_UTR_variant	4/4	1	NM_213607.3	P1
GFAP	ENST00000588735.3	c.*3797G>A		3_prime_UTR_variant	9/9	1	NM_002055.5	P1

Frequencies

GnomAD3 genomes AF: 0.000243 AC: 37 AN: 152164 Hom.: 3 Cov.: 32

Gnomad AFR AF: 0.0000724

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000193

Gnomad SAS AF: 0.00642

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.000244 AC: 294 AN: 1207354 Hom.: 1 Cov.: 31 AF XY: 0.000325 AC XY: 188 AN XY: 579148

Gnomad4 AFR exome AF: 0.0000381

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000960

Gnomad4 SAS exome AF: 0.00544

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000241

Gnomad4 OTH exome AF: 0.000521

GnomAD4 genome AF: 0.000250 AC: 38 AN: 152282 Hom.: 3 Cov.: 32 AF XY: 0.000376 AC XY: 28 AN XY: 74464

Gnomad4 AFR AF: 0.0000722

Gnomad4 AMR AF: 0.0000654

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000193

Gnomad4 SAS AF: 0.00663

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000277 Hom.: 0

Bravo AF: 0.0000945

Asia WGS AF: 0.00260 AC: 9 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Primary ciliary dyskinesia 17 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.87
CADD	Benign	12
DANN	Benign	0.83

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: rs542384155; hg19: chr17-42980918;