7-155803249-G-A

Position:

• chr7-155803249-G-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The ENST00000297261.7(SHH):​c.1040C>T​(p.Pro347Leu) 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. 12/20 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P347Q) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: SHH ENST00000297261.7 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 9.17

Genes affected

SHH (HGNC:10848): (sonic hedgehog signaling molecule) This gene encodes a protein that is instrumental in patterning the early embryo. It has been implicated as the key inductive signal in patterning of the ventral neural tube, the anterior-posterior limb axis, and the ventral somites. Of three human proteins showing sequence and functional similarity to the sonic hedgehog protein of Drosophila, this protein is the most similar. The protein is made as a precursor that is autocatalytically cleaved; the N-terminal portion is soluble and contains the signalling activity while the C-terminal portion is involved in precursor processing. More importantly, the C-terminal product covalently attaches a cholesterol moiety to the N-terminal product, restricting the N-terminal product to the cell surface and preventing it from freely diffusing throughout the developing embryo. Defects in this protein or in its signalling pathway are a cause of holoprosencephaly (HPE), a disorder in which the developing forebrain fails to correctly separate into right and left hemispheres. HPE is manifested by facial deformities. It is also thought that mutations in this gene or in its signalling pathway may be responsible for VACTERL syndrome, which is characterized by vertebral defects, anal atresia, tracheoesophageal fistula with esophageal atresia, radial and renal dysplasia, cardiac anomalies, and limb abnormalities. Additionally, mutations in a long range enhancer located approximately 1 megabase upstream of this gene disrupt limb patterning and can result in preaxial polydactyly. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in ENST00000297261.7
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-155803249-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 282694.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.994
• PP5: Variant 7-155803249-G-A is Pathogenic according to our data. Variant chr7-155803249-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 545575.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SHH	NM_000193.4	c.1040C>T	p.Pro347Leu	missense_variant	3/3	ENST00000297261.7	NP_000184.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SHH	ENST00000297261.7	c.1040C>T	p.Pro347Leu	missense_variant	3/3	1	NM_000193.4	ENSP00000297261	P1
SHH	ENST00000430104.5	c.302-3004C>T		intron_variant		1		ENSP00000396621
SHH	ENST00000435425.1	c.302-2652C>T		intron_variant, NMD_transcript_variant		1		ENSP00000413871
SHH	ENST00000441114.5	c.302-2582C>T		intron_variant, NMD_transcript_variant		1		ENSP00000410546

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1364358 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 675944

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

SHH-related disorder Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jan 18, 2023

Variant summary: SHH c.1040C>T (p.Pro347Leu) results in a non-conservative amino acid change located in the Hint domain (IPR001767) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 130974 control chromosomes (gnomAD). c.1040C>T has been reported in the literature in an individual affected with holoprosencephaly (Roessler_2009, Mercier_2011), and further information submitted to ClinVar from this lab (Muenke lab, National Institutes of Health) has indicated that this was a de novo occurrence. These data suggest that the variant may be associated with holoprosencephaly, a SHH-Related Disorder. A study examining the variant in a zebrafish model found that unlike the wild-type protein, Pro347Leu was unable to rescue the null phenotype, indicating that it impairs protein function. Furthermore, other variants which affect the same residue (e.g. P347R, P347Q) have also been reported in holoproencephaly patients (Roessler_2009, HGMD database). One submitter has provided a clinical-significance assessment for this variant to ClinVar after 2014 and classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Jun 12, 2023

Identified in a patient with holoprosencephaly in published literature (Roessler et al., 2009); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 19603532, 32939873) -

Holoprosencephaly 3 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Muenke lab, National Institutes of Health

Mar 15, 2017

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.93
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.59
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	1.0	D
Eigen	Pathogenic	0.84
Eigen_PC	Pathogenic	0.71
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.96	D
M_CAP	Pathogenic	0.99	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.85	D
MutationAssessor	Pathogenic	3.6	H
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.92	D
PROVEAN	Pathogenic	-8.5	D
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.94
MutPred		0.93		Loss of glycosylation at P347 (P = 0.0258);
MVP		1.0
ClinPred		1.0	D
GERP RS		3.6
Varity_R		0.99
gMVP		0.96

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: rs886042458; hg19: chr7-155595943;