X-13753412-G-C

Variant names:

• chrX-13753412-G-C
• rs312262864
• NM_003611.3:c.1100G>C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_003611.3(OFD1):​c.1100G>C​(p.Arg367Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R367G) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 22)
• Consequence: OFD1 NM_003611.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.170
• Publications: 2 publications found

Genes affected

OFD1 (HGNC:2567): (OFD1 centriole and centriolar satellite protein) This gene is located on the X chromosome and encodes a centrosomal protein. A knockout mouse model has been used to study the effect of mutations in this gene. The mouse gene is also located on the X chromosome, however, unlike the human gene it is not subject to X inactivation. Mutations in this gene are associated with oral-facial-digital syndrome type I and Simpson-Golabi-Behmel syndrome type 2. Many pseudogenes have been identified; a single pseudogene is found on chromosome 5 while as many as fifteen have been found on the Y chromosome. [provided by RefSeq, Aug 2016]

OFD1 Gene-Disease associations (from GenCC):

• ciliopathy

  Inheritance: XL Classification: DEFINITIVE Submitted by: ClinGen
• Joubert syndrome 10

  Inheritance: XL Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• orofaciodigital syndrome I

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Labcorp Genetics (formerly Invitae)
• retinitis pigmentosa 23

  Inheritance: XL Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• primary ciliary dyskinesia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• retinitis pigmentosa

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• orofaciodigital syndrome type 6

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• Simpson-Golabi-Behmel syndrome type 2

  Inheritance: XL Classification: LIMITED Submitted by: G2P

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
OFD1	NM_003611.3	c.1100G>C	p.Arg367Pro	missense_variant	Exon 11 of 23	ENST00000340096.11	NP_003602.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
OFD1	ENST00000340096.11	c.1100G>C	p.Arg367Pro	missense_variant	Exon 11 of 23	1	NM_003611.3	ENSP00000344314.6

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 22

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Joubert syndrome;C1510460:Orofaciodigital syndrome I Uncertain:1

Sep 08, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. 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. This variant has not been reported in the literature in individuals affected with OFD1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces arginine, which is basic and polar, with proline, which is neutral and non-polar, at codon 367 of the OFD1 protein (p.Arg367Pro).

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.87
BayesDel_addAF	Uncertain	0.098	D
BayesDel_noAF	Benign	-0.10
CADD	Benign	16
DANN	Benign	0.96
DEOGEN2	Uncertain	0.46	T;.;.;T
LIST_S2	Uncertain	0.89	D;D;T;D
M_CAP	Pathogenic	0.37	D
MetaRNN	Uncertain	0.50	T;T;T;T
MetaSVM	Uncertain	0.57	D
MutationAssessor	Uncertain	2.3	M;.;.;.
PhyloP100		-0.17
PrimateAI	Benign	0.26	T
PROVEAN	Uncertain	-3.3	D;D;D;D
Sift	Uncertain	0.0070	D;D;D;D
Sift4G	Uncertain	0.013	D;D;D;D
Vest4		0.47
ClinPred		0.94	D
GERP RS		-2.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0
Varity_R		0.64
gMVP		0.60
Mutation Taster		=60/40	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs312262864; hg19: chrX-13771531;