rs1555542868

chr16-67660465-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The ENST00000219251.13(ACD):c.-245G>A variant causes a 5 prime UTR 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. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: ACD ENST00000219251.13 5_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.05

Genes affected

ACD (HGNC:25070): (ACD shelterin complex subunit and telomerase recruitment factor) This gene encodes a protein that is involved in telomere function. This protein is one of six core proteins in the telosome/shelterin telomeric complex, which functions to maintain telomere length and to protect telomere ends. Through its interaction with other components, this protein plays a key role in the assembly and stabilization of this complex, and it mediates the access of telomerase to the telomere. Multiple transcript variants encoding different isoforms have been found for this gene. This gene, which is also referred to as TPP1, is distinct from the unrelated TPP1 gene on chromosome 11, which encodes tripeptidyl-peptidase I. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.06166935).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ACD	ENST00000219251.13	c.-245G>A		5_prime_UTR_variant	1/12	2
ACD	ENST00000602382.6	c.-245G>A		5_prime_UTR_variant	1/12	5
ACD	ENST00000602860.6	n.299G>A		non_coding_transcript_exon_variant	1/9	5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Dyskeratosis congenita, autosomal dominant 6 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Apr 06, 2023

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 output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The tyrosine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. ClinVar contains an entry for this variant (Variation ID: 542414). This variant has not been reported in the literature in individuals affected with ACD-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces cysteine, which is neutral and slightly polar, with tyrosine, which is neutral and polar, at codon 5 of the ACD protein (p.Cys5Tyr). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.14	T
BayesDel_noAF	Benign	-0.44
Cadd	Benign	3.4
Dann	Benign	0.87
DEOGEN2	Benign	0.15	T;.
Eigen	Benign	-1.2
Eigen_PC	Benign	-1.2
FATHMM_MKL	Benign	0.054	N
LIST_S2	Benign	0.33	T;.
M_CAP	Benign	0.0086	T
MetaRNN	Benign	0.062	T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.0	N;N
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.48	T
Polyphen		0.0020	B;B
Vest4		0.097
MutPred		0.23		Gain of phosphorylation at C5 (P = 0.0319);Gain of phosphorylation at C5 (P = 0.0319);
MVP		0.22
ClinPred		0.15	T
GERP RS		-0.78
Varity_R		0.46
gMVP		0.034

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: rs1555542868; hg19: chr16-67694368;