18-70168871-G-T

Variant names:

• chr18-70168871-G-T
• rs777233196
• NM_173630.4:c.1673C>A

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001318520.2(RTTN):​c.-975C>A variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000343 in 1,456,662 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 Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: RTTN NM_001318520.2 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.0590

Genes affected

RTTN (HGNC:18654): (rotatin) This gene encodes a large protein whose specific function is unknown. Absence of the orthologous protein in mouse results in embryonic lethality with deficient axial rotation, abnormal differentiation of the neural tube, and randomized looping of the heart tube during development. In human, mutations in this gene are associated with polymicrogyria with seizures. In human fibroblasts this protein localizes at the ciliary basal bodies. Given the intracellular localization of this protein and the phenotypic effects of mutations, this gene is suspected of playing a role in the maintenance of normal ciliary structure which in turn effects the developmental process of left-right organ specification, axial rotation, and perhaps notochord development. [provided by RefSeq, Jan 2013]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.18286043).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
RTTN	NM_173630.4	c.1673C>A	p.Ser558Tyr	missense_variant	Exon 12 of 49	ENST00000640769.2	NP_775901.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
RTTN	ENST00000640769.2	c.1673C>A	p.Ser558Tyr	missense_variant	Exon 12 of 49	2	NM_173630.4	ENSP00000491507.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000343 AC: 5 AN: 1456662 Hom.: 0 Cov.: 30 AF XY: 0.00000414 AC XY: 3 AN XY: 724216

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000360

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Nov 16, 2015

Genetic Services Laboratory, University of Chicago

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Uncertain:1

-

Breakthrough Genomics, Breakthrough Genomics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: not provided

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.098
BayesDel_addAF	Benign	-0.18	T
BayesDel_noAF	Benign	-0.50
CADD	Benign	14
DANN	Uncertain	0.99
DEOGEN2	Benign	0.11	T;.;.
Eigen	Uncertain	0.24
Eigen_PC	Uncertain	0.27
FATHMM_MKL	Benign	0.68	D
LIST_S2	Benign	0.66	T;T;T
M_CAP	Benign	0.014	T
MetaRNN	Benign	0.18	T;T;T
MetaSVM	Benign	-0.80	T
MutationAssessor	Benign	1.9	M;M;.
PrimateAI	Benign	0.34	T
PROVEAN	Benign	-1.2	.;N;.
REVEL	Benign	0.075
Sift	Benign	0.14	.;T;.
Sift4G	Benign	0.079	.;T;.
Polyphen		0.81	P;.;.
Vest4		0.21
MutPred		0.36		Gain of methylation at K562 (P = 0.0468);Gain of methylation at K562 (P = 0.0468);.;
MVP		0.33
MPC		0.18
ClinPred		0.67	D
GERP RS		4.8
Varity_R		0.065
gMVP		0.25

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: rs777233196; hg19: chr18-67836107;