chr16-56567810-T-A

Variant names:

• chr16-56567810-T-A
• rs666647
• NM_032935.3:c.91T>A

Variant summary

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

The NM_032935.3(MT4):​c.91T>A​(p.Trp31Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 14/23 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 30)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: MT4 NM_032935.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.436
• Publications: 22 publications found

Genes affected

MT4 (HGNC:18705): (metallothionein 4) Predicted to enable metal ion binding activity. Predicted to be involved in cellular response to metal ion; cellular zinc ion homeostasis; and detoxification of copper ion. Predicted to act upstream of or within cellular metal ion homeostasis. Predicted to be active in cytoplasm and nucleus. [provided by Alliance of Genome Resources, Apr 2022]

BBS2 (HGNC:967): (Bardet-Biedl syndrome 2) This gene is a member of the Bardet-Biedl syndrome (BBS) gene family. Bardet-Biedl syndrome is an autosomal recessive disorder characterized by severe pigmentary retinopathy, obesity, polydactyly, renal malformation and cognitive disability. The proteins encoded by BBS gene family members are structurally diverse and the similar phenotypes exhibited by mutations in BBS gene family members is likely due to their shared roles in cilia formation and function. Many BBS proteins localize to the basal bodies, ciliary axonemes, and pericentriolar regions of cells. BBS proteins may also be involved in intracellular trafficking via microtubule-related transport. The protein encoded by this gene forms a multiprotein BBSome complex with seven other BBS proteins.[provided by RefSeq, Oct 2014]

BBS2 Gene-Disease associations (from GenCC):

• Bardet-Biedl syndrome 2

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Myriad Women’s Health
• BBS2-related ciliopathy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• retinitis pigmentosa 74

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• retinitis pigmentosa

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Bardet-Biedl syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

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

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

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_032935.3. 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
	MT4	NM_032935.3	MANE Select	c.91T>A	p.Trp31Arg	missense	Exon 2 of 3	NP_116324.2	P47944

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MT4	ENST00000219162.4	TSL:1 MANE Select	c.91T>A	p.Trp31Arg	missense	Exon 2 of 3	ENSP00000219162.3	P47944
	BBS2	ENST00000682930.1		c.42+2865A>T		intron	N/A	ENSP00000507981.1	A0A804HKL9

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD4 exome Data not reliable, filtered out with message: AC0;AS_VQSR AF: 0.00 AC: 0 AN: 1460502 Hom.: 0 Cov.: 36 AF XY: 0.00 AC XY: 0 AN XY: 726566

African (AFR) AF: 0.00 AC: 0 AN: 33446

American (AMR) AF: 0.00 AC: 0 AN: 44676

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26104

East Asian (EAS) AF: 0.00 AC: 0 AN: 39662

South Asian (SAS) AF: 0.00 AC: 0 AN: 86222

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53304

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5760

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111012

Other (OTH) AF: 0.00 AC: 0 AN: 60316

GnomAD4 genome Cov.: 30

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.052
BayesDel_addAF	Benign	-0.31	T
BayesDel_noAF	Benign	-0.68
CADD	Benign	16
DANN	Benign	0.72
DEOGEN2	Benign	0.069	T
Eigen	Benign	-0.68
Eigen_PC	Benign	-0.58
FATHMM_MKL	Benign	0.063	N
LIST_S2	Benign	0.049	T
M_CAP	Benign	0.0039	T
MetaRNN	Benign	0.15	T
MetaSVM	Benign	-1.0	T
PhyloP100		0.44
PrimateAI	Benign	0.27	T
PROVEAN	Benign	4.7	N
REVEL	Benign	0.071
Sift	Benign	0.85	T
Sift4G	Benign	0.32	T
Polyphen		0.0	B
Vest4		0.044
MutPred		0.29		Loss of ubiquitination at K28 (P = 0.0367)
MVP		0.014
MPC		0.021
ClinPred		0.56	D
GERP RS		4.7
Varity_R		0.046
gMVP		0.092

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.22		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.22		Position offset: 6

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs666647; hg19: chr16-56601722;