5-55220448-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_001190787.3(MCIDAS):c.1076G>T(p.Arg359Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000145 in 1,383,790 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MCIDAS NM_001190787.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.64

Genes affected

MCIDAS (HGNC:40050): (multiciliate differentiation and DNA synthesis associated cell cycle protein) This gene encodes a member of the geminin family of proteins. The encoded nuclear protein is required for the generation of multiciliated cells in respiratory epithelium. Mutations in this gene cause a rare mucociliary clearance disorder associated with recurring respiratory infections in human patients, known as reduced generation of multiple motile cilia (RGMC). [provided by RefSeq, Sep 2016]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.799

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MCIDAS	NM_001190787.3	c.1076G>T	p.Arg359Leu	missense_variant	7/7	ENST00000513312.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MCIDAS	ENST00000513312.3	c.1076G>T	p.Arg359Leu	missense_variant	7/7	1	NM_001190787.3	P1
MCIDAS	ENST00000513468.5	c.*540G>T		3_prime_UTR_variant, NMD_transcript_variant	7/7	5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000145 AC: 2 AN: 1383790 Hom.: 0 Cov.: 30 AF XY: 0.00000293 AC XY: 2 AN XY: 682840

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: 0.0000252

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Primary ciliary dyskinesia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Mar 27, 2018

This sequence change replaces arginine with leucine at codon 359 of the MCIDAS protein (p.Arg359Leu). The arginine residue is highly conserved and there is a moderate physicochemical difference between arginine and leucine. While this variant is not present in population databases, the frequency information is unreliable, as metrics indicate poor data quality at this position in the ExAC database. This variant has not been reported in the literature in individuals with MCIDAS-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.73
BayesDel_addAF	Pathogenic	0.38	D
BayesDel_noAF	Pathogenic	0.31
Cadd	Pathogenic	32
Dann	Uncertain	1.0
DEOGEN2	Benign	0.22	T
Eigen	Uncertain	0.61
Eigen_PC	Uncertain	0.59
FATHMM_MKL	Uncertain	0.85	D
LIST_S2	Benign	0.83	T
M_CAP	Pathogenic	0.33	D
MetaRNN	Pathogenic	0.80	D
MetaSVM	Uncertain	-0.27	T
MutationAssessor	Uncertain	2.1	M
MutationTaster	Benign	0.99	D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-2.5	D
REVEL	Uncertain	0.32
Sift	Uncertain	0.0020	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.78
MutPred		0.55		Gain of sheet (P = 0.0221);
MVP		0.43
ClinPred		0.99	D
GERP RS		4.8
Varity_R		0.31
gMVP		0.82

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: rs1561114448; hg19: chr5-54516276;