11-71441413-C-G

Variant names:

• chr11-71441413-C-G
• rs777425801
• NM_001360.3:c.440G>C

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PM5 PP3_Moderate

The NM_001360.3(DHCR7):​c.440G>C​(p.Gly147Ala) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,518 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G147S) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: DHCR7 NM_001360.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.89
• Publications: 0 publications found

Genes affected

DHCR7 (HGNC:2860): (7-dehydrocholesterol reductase) This gene encodes an enzyme that removes the C(7-8) double bond in the B ring of sterols and catalyzes the conversion of 7-dehydrocholesterol to cholesterol. This gene is ubiquitously expressed and its transmembrane protein localizes to the endoplasmic reticulum membrane and nuclear outer membrane. Mutations in this gene cause Smith-Lemli-Opitz syndrome (SLOS); a syndrome that is metabolically characterized by reduced serum cholesterol levels and elevated serum 7-dehydrocholesterol levels and phenotypically characterized by cognitive disability, facial dysmorphism, syndactyly of second and third toes, and holoprosencephaly in severe cases to minimal physical abnormalities and near-normal intelligence in mild cases. Alternative splicing results in multiple transcript variants that encode the same protein.[provided by RefSeq, Aug 2009]

DHCR7 Gene-Disease associations (from GenCC):

• Smith-Lemli-Opitz syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), G2P, Myriad Women’s Health, Orphanet, ClinGen

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in NM_001360.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr11-71441414-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1740285.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.913

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001360.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DHCR7	NM_001360.3	MANE Select	c.440G>C	p.Gly147Ala	missense	Exon 6 of 9	NP_001351.2
	DHCR7	NM_001425107.1		c.440G>C	p.Gly147Ala	missense	Exon 6 of 10	NP_001412036.1
	DHCR7	NM_001425108.1		c.476G>C	p.Gly159Ala	missense	Exon 6 of 9	NP_001412037.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DHCR7	ENST00000355527.8	TSL:1 MANE Select	c.440G>C	p.Gly147Ala	missense	Exon 6 of 9	ENSP00000347717.4
	DHCR7	ENST00000407721.6	TSL:1	c.440G>C	p.Gly147Ala	missense	Exon 6 of 9	ENSP00000384739.2
	DHCR7	ENST00000685320.1		c.-146G>C		5_prime_UTR	Exon 5 of 8	ENSP00000509319.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461518 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 727062

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33470

American (AMR) AF: 0.00 AC: 0 AN: 44674

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86226

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53406

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111770

Other (OTH) AF: 0.00 AC: 0 AN: 60376

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.87
BayesDel_addAF	Pathogenic	0.37	D
BayesDel_noAF	Pathogenic	0.29
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.98	D
Eigen	Uncertain	0.35
Eigen_PC	Uncertain	0.27
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.35	D
MetaRNN	Pathogenic	0.91	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Benign	1.9	L
PhyloP100		6.9
PrimateAI	Uncertain	0.66	T
PROVEAN	Pathogenic	-5.8	D
REVEL	Pathogenic	0.77
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.88
MutPred		0.59		Loss of methylation at K142 (P = 0.1209)
MVP		0.98
MPC		0.58
ClinPred		1.0	D
GERP RS		4.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.90
gMVP		0.97
Mutation Taster		=20/80	disease causing

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

Other links and lift over

dbSNP: rs777425801; hg19: chr11-71152459;