17-68537631-G-A

Variant summary

Our verdict is Benign. Variant got -14 ACMG points: 2P and 16B. PM2 BP4_Strong BP6_Very_Strong BS1

The NM_017565.4(FAM20A):c.1472C>T(p.Thr491Ile) variant causes a missense change. The variant allele was found at a frequency of 0.000112 in 1,613,792 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.00019 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00010 (0 hom.)
• Consequence: FAM20A NM_017565.4 missense
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:2
• Conservation: PhyloP100: 6.46

Genes affected

FAM20A (HGNC:23015): (FAM20A golgi associated secretory pathway pseudokinase) This locus encodes a protein that is likely secreted and may function in hematopoiesis. A mutation at this locus has been associated with amelogenesis imperfecta and gingival hyperplasia syndrome. Alternatively spliced transcript variants have been identified. [provided by RefSeq, Aug 2011]

PRKAR1A (HGNC:9388): (protein kinase cAMP-dependent type I regulatory subunit alpha) cAMP is a signaling molecule important for a variety of cellular functions. cAMP exerts its effects by activating the cAMP-dependent protein kinase, which transduces the signal through phosphorylation of different target proteins. The inactive kinase holoenzyme is a tetramer composed of two regulatory and two catalytic subunits. cAMP causes the dissociation of the inactive holoenzyme into a dimer of regulatory subunits bound to four cAMP and two free monomeric catalytic subunits. Four different regulatory subunits and three catalytic subunits have been identified in humans. This gene encodes one of the regulatory subunits. This protein was found to be a tissue-specific extinguisher that down-regulates the expression of seven liver genes in hepatoma x fibroblast hybrids. Mutations in this gene cause Carney complex (CNC). This gene can fuse to the RET protooncogene by gene rearrangement and form the thyroid tumor-specific chimeric oncogene known as PTC2. A nonconventional nuclear localization sequence (NLS) has been found for this protein which suggests a role in DNA replication via the protein serving as a nuclear transport protein for the second subunit of the Replication Factor C (RFC40). Several alternatively spliced transcript variants encoding two different isoforms have been observed. [provided by RefSeq, Jan 2013]

ACMG classification

Verdict is Benign. Variant got -14 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.013489485).
• BP6: Variant 17-68537631-G-A is Benign according to our data. Variant chr17-68537631-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 1597393.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BS1: Variant frequency is greater than expected in population eas. gnomad4 allele frequency = 0.00019 (29/152330) while in subpopulation EAS AF= 0.00501 (26/5186). AF 95% confidence interval is 0.00351. There are 0 homozygotes in gnomad4. There are 20 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FAM20A	NM_017565.4	c.1472C>T	p.Thr491Ile	missense_variant	11/11	ENST00000592554.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FAM20A	ENST00000592554.2	c.1472C>T	p.Thr491Ile	missense_variant	11/11	1	NM_017565.4	P1

Frequencies

GnomAD3 genomes AF: 0.000191 AC: 29 AN: 152212 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000482

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00500

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000284 AC: 71 AN: 249958 Hom.: 0 AF XY: 0.000259 AC XY: 35 AN XY: 135080

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000290

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00370

Gnomad SAS exome AF: 0.0000330

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000885

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.000104 AC: 152 AN: 1461462 Hom.: 0 Cov.: 35 AF XY: 0.0000880 AC XY: 64 AN XY: 726924

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00338

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.000182

GnomAD4 genome AF: 0.000190 AC: 29 AN: 152330 Hom.: 0 Cov.: 32 AF XY: 0.000268 AC XY: 20 AN XY: 74504

Gnomad4 AFR AF: 0.0000481

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00501

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000202 Hom.: 0

Bravo AF: 0.000374

ExAC AF: 0.000255 AC: 31

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Likely benign

Submissions summary: Benign:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Aug 27, 2023

- -

Amelogenesis imperfecta type 1G Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Nov 30, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.30
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Uncertain	0.050
Cadd	Uncertain	24
Dann	Uncertain	1.0
Eigen	Uncertain	0.61
Eigen_PC	Uncertain	0.62
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.86	D;D
M_CAP	Benign	0.028	D
MetaRNN	Benign	0.013	T;T
MetaSVM	Benign	-0.56	T
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.57	T
Sift4G	Benign	0.45	T;T
Polyphen		1.0	.;D
Vest4		0.28
MVP		0.70
MPC		0.26
ClinPred		0.15	T
GERP RS		4.5
Varity_R		0.32
gMVP		0.73

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: rs182816928; hg19: chr17-66533772;