rs16973034

Positions:

• chr17-68538004-A-C
• chr17-68538004-A-G

Variant summary

Our verdict is Benign. Variant got -12 ACMG points: 0P and 12B. BP4_Strong BS1 BS2

The NM_017565.4(FAM20A):​c.1362-263T>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00404 in 152,264 control chromosomes in the GnomAD database, including 3 homozygotes. 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: 𝑓 0.0040 (3 hom., cov: 33)
• Consequence: FAM20A NM_017565.4 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.648

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 -12 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.89).
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00404 (615/152264) while in subpopulation NFE AF= 0.00723 (492/68018). AF 95% confidence interval is 0.00671. There are 3 homozygotes in gnomad4. There are 274 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
• BS2: High Homozygotes in GnomAd4 at 3 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FAM20A	NM_017565.4	c.1362-263T>G		intron_variant		ENST00000592554.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FAM20A	ENST00000592554.2	c.1362-263T>G		intron_variant		1	NM_017565.4	P1

Frequencies

GnomAD3 genomes AF: 0.00404 AC: 615 AN: 152146 Hom.: 3 Cov.: 33

Gnomad AFR AF: 0.00128

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00281

Gnomad ASJ AF: 0.000288

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000829

Gnomad FIN AF: 0.000943

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00723

Gnomad OTH AF: 0.00575

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

GnomAD4 genome AF: 0.00404 AC: 615 AN: 152264 Hom.: 3 Cov.: 33 AF XY: 0.00368 AC XY: 274 AN XY: 74446

Gnomad4 AFR AF: 0.00128

Gnomad4 AMR AF: 0.00281

Gnomad4 ASJ AF: 0.000288

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000830

Gnomad4 FIN AF: 0.000943

Gnomad4 NFE AF: 0.00723

Gnomad4 OTH AF: 0.00569

Alfa AF: 0.000653 Hom.: 48

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.89
CADD	Benign	0.074
DANN	Benign	0.53

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.070		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: rs16973034; hg19: chr17-66534145;