rs35313369

Positions:

• chr18-70024789-C-T

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 2P and 8B. PM2 BP4_Moderate BP6 BP7 BS1

The NM_173630.4(RTTN):​c.5883G>A​(p.Leu1961Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000344 in 1,613,978 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.0018 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00020 (1 hom.)
• Consequence: RTTN NM_173630.4 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:3
• Conservation: PhyloP100: 0.607

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]

RTTN (HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.46).
• BP6: Variant 18-70024789-C-T is Benign according to our data. Variant chr18-70024789-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 212084.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=1, Benign=1}.
• BP7: Synonymous conserved (PhyloP=0.607 with no splicing effect.
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00175 (267/152256) while in subpopulation AFR AF= 0.00623 (259/41546). AF 95% confidence interval is 0.00561. There are 0 homozygotes in gnomad4. There are 125 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	Protein	UniProt
RTTN	NM_173630.4	c.5883G>A	p.Leu1961Leu	synonymous_variant	44/49	ENST00000640769.2	NP_775901.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RTTN	ENST00000640769.2	c.5883G>A	p.Leu1961Leu	synonymous_variant	44/49	2	NM_173630.4	ENSP00000491507.1

Frequencies

GnomAD3 genomes AF: 0.00176 AC: 268 AN: 152138 Hom.: 1 Cov.: 32

Gnomad AFR AF: 0.00628

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000393

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.000479

GnomAD3 exomes AF: 0.000474 AC: 118 AN: 249186 Hom.: 0 AF XY: 0.000333 AC XY: 45 AN XY: 135158

Gnomad AFR exome AF: 0.00620

Gnomad AMR exome AF: 0.000580

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000885

Gnomad OTH exome AF: 0.000165

GnomAD4 exome AF: 0.000197 AC: 288 AN: 1461722 Hom.: 1 Cov.: 30 AF XY: 0.000158 AC XY: 115 AN XY: 727166

Gnomad4 AFR exome AF: 0.00636

Gnomad4 AMR exome AF: 0.000693

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000989

Gnomad4 OTH exome AF: 0.000480

GnomAD4 genome AF: 0.00175 AC: 267 AN: 152256 Hom.: 0 Cov.: 32 AF XY: 0.00168 AC XY: 125 AN XY: 74444

Gnomad4 AFR AF: 0.00623

Gnomad4 AMR AF: 0.000392

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.000474

Alfa AF: 0.00111 Hom.: 0

Bravo AF: 0.00216

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:3

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Benign:2

Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 22, 2024	- -
Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Dec 28, 2020	- -

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Genetic Services Laboratory, University of Chicago

May 01, 2015

- -

RTTN-related disorder Benign:1

Likely benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

May 07, 2019

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.46
CADD	Benign	9.2
DANN	Benign	0.71

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: rs35313369; hg19: chr18-67692025;