2-1494027-G-C

Variant names:

• chr2-1494027-G-C
• rs140124953
• NM_001206744.2:c.1994G>C

Variant summary

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

The NM_001206744.2(TPO):​c.1994G>C​(p.Arg665Pro) 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. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R665W) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TPO NM_001206744.2 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.31
• Publications: 8 publications found

Genes affected

TPO (HGNC:12015): (thyroid peroxidase) This gene encodes a membrane-bound glycoprotein. The encoded protein acts as an enzyme and plays a central role in thyroid gland function. The protein functions in the iodination of tyrosine residues in thyroglobulin and phenoxy-ester formation between pairs of iodinated tyrosines to generate the thyroid hormones, thyroxine and triiodothyronine. Mutations in this gene are associated with several disorders of thyroid hormonogenesis, including congenital hypothyroidism, congenital goiter, and thyroid hormone organification defect IIA. Multiple transcript variants encoding distinct isoforms have been identified for this gene, but the full-length nature of some variants has not been determined. [provided by RefSeq, May 2011]

TPO Gene-Disease associations (from GenCC):

• thyroid dyshormonogenesis 2A

  Inheritance: AR Classification: STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae)
• familial thyroid dyshormonogenesis

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000231482 (HGNC:):

LALTOP (HGNC:58132):

ACMG classification

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

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_001206744.2
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-1494026-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 2734130.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.984

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001206744.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TPO	NM_001206744.2	MANE Select	c.1994G>C	p.Arg665Pro	missense	Exon 11 of 17	NP_001193673.1	P07202-1
	TPO	NM_000547.6		c.1994G>C	p.Arg665Pro	missense	Exon 11 of 17	NP_000538.3
	TPO	NM_175721.3		c.1994G>C	p.Arg665Pro	missense	Exon 10 of 15	NP_783652.1	P07202-4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TPO	ENST00000329066.9	TSL:1 MANE Select	c.1994G>C	p.Arg665Pro	missense	Exon 11 of 17	ENSP00000329869.4	P07202-1
	TPO	ENST00000345913.8	TSL:1	c.1994G>C	p.Arg665Pro	missense	Exon 11 of 17	ENSP00000318820.7	P07202-1
	TPO	ENST00000382201.7	TSL:1	c.1823G>C	p.Arg608Pro	missense	Exon 10 of 16	ENSP00000371636.3	P07202-2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000194 Hom.: 0

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.32
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.83	D
Eigen	Pathogenic	0.84
Eigen_PC	Pathogenic	0.69
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D
M_CAP	Pathogenic	0.63	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Uncertain	0.71	D
MutationAssessor	Pathogenic	4.4	H
PhyloP100		7.3
PrimateAI	Uncertain	0.65	T
PROVEAN	Pathogenic	-6.9	D
REVEL	Pathogenic	0.86
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.96
MutPred		0.87		Loss of stability (P = 0.0203)
MVP		0.94
MPC		0.82
ClinPred		1.0	D
GERP RS		4.8
Varity_R		0.99
gMVP		0.98
Mutation Taster		=3/97	disease causing

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: rs140124953; hg19: chr2-1497799;