Genetic Variant MAN1B1:c.1255-4G>T (chr9-137106121-G-T) – ACMG Classification: Likely_benign (-3 pts)

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2BP4_StrongBP6

The NM_016219.5(MAN1B1):c.1255-4G>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000248 in 1,611,712 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (no stars).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 34)

Exomes 𝑓: 0.000027 ( 0 hom. )

Consequence

MAN1B1
NM_016219.5 splice_region, intron

Scores

Splicing: ADA: 0.0001066

Clinical Significance

Likely benign no assertion criteria provided B:1

Conservation

PhyloP100: 0.0930

Variant links:

Genes affected

MAN1B1 (HGNC:6823): (mannosidase alpha class 1B member 1) This gene encodes an enzyme belonging to the glycosyl hydrolase 47 family. This enzyme functions in N-glycan biosynthesis, and is a class I alpha-1,2-mannosidase that specifically converts Man9GlcNAc to Man8GlcNAc isomer B. It is required for N-glycan trimming to Man5-6GlcNAc2 in the endoplasmic-reticulum-associated degradation pathway. Mutations in this gene cause autosomal-recessive intellectual disability. Alternative splicing results in multiple transcript variants. A related pseudogene has been identified on chromosome 11. [provided by RefSeq, Dec 2011]

MAN1B1 links:

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ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.82).

BP6

Variant 9-137106121-G-T is Benign according to our data. Variant chr9-137106121-G-T is described in ClinVar as [Likely_benign]. Clinvar id is 3034572.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	Effect	Exon rank	MANE	Protein	UniProt
MAN1B1	NM_016219.5 link	c.1255-4G>T	splice_region_variant, intron_variant	Intron 8 of 12	ENST00000371589.9	NP_057303.2	Q9UKM7
MAN1B1	XM_006716945.5 link	c.1255-4G>T	splice_region_variant, intron_variant	Intron 8 of 11		XP_006717008.1	H0YG20
MAN1B1	NR_045720.2 link	n.1270-4G>T	splice_region_variant, intron_variant	Intron 8 of 12
MAN1B1	NR_045721.2 link	n.1401-4G>T	splice_region_variant, intron_variant	Intron 9 of 13

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MAN1B1	ENST00000371589.9 link	c.1255-4G>T		splice_region_variant, intron_variant	Intron 8 of 12	1	NM_016219.5	ENSP00000360645.4		Q9UKM7

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152226

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000162

AC:

AN:

247070

Hom.:

AF XY:

0.00000744

AC XY:

AN XY:

134324

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000362

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000267

AC:

AN:

1459486

Hom.:

Cov.:

AF XY:

0.0000262

AC XY:

AN XY:

726070

show subpopulations

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:

0.0000324

Gnomad4 OTH exome

AF:

0.0000497

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152226

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74350

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000434

Hom.:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: no assertion criteria provided

LINK: link

Submissions by phenotype

MAN1B1-related disorder

Benign:1

Jul 31, 2019

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.82

CADD

Benign

2.1

DANN

Benign

0.78

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.00011

dbscSNV1_RF

Benign

0.010

SpliceAI score (max)

0.11

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over