9-137087089-C-T

Variant names:

• chr9-137087089-C-T
• rs1588577872
• NM_016219.5:c.90C>T

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 2P and 3B. PM2 BP4_Moderate BP7

The NM_016219.5(MAN1B1):​c.90C>T​(p.Ala30Ala) variant causes a synonymous 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. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. A30A) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 34)
• Consequence: MAN1B1 NM_016219.5 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.432
• Publications: 0 publications found

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 Gene-Disease associations (from GenCC):

• MAN1B1-congenital disorder of glycosylation

  Inheritance: AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• Rafiq syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, PanelApp Australia, Labcorp Genetics (formerly Invitae), Ambry Genetics
• autosomal recessive non-syndromic intellectual disability

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (REVEL=0.058).
• BP7: Synonymous conserved (PhyloP=-0.432 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MAN1B1	NM_016219.5	c.90C>T	p.Ala30Ala	synonymous_variant	Exon 1 of 13	ENST00000371589.9	NP_057303.2
MAN1B1	XM_006716945.5	c.90C>T	p.Ala30Ala	synonymous_variant	Exon 1 of 12		XP_006717008.1
MAN1B1	NR_045720.2	n.105C>T		non_coding_transcript_exon_variant	Exon 1 of 13
MAN1B1	NR_045721.2	n.105C>T		non_coding_transcript_exon_variant	Exon 1 of 14

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MAN1B1	ENST00000371589.9	c.90C>T	p.Ala30Ala	synonymous_variant	Exon 1 of 13	1	NM_016219.5	ENSP00000360645.4

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 34

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.64
CADD	Benign	7.6
DANN	Benign	0.88
PhyloP100		-0.43
PromoterAI		-0.083	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.1

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: rs1588577872; hg19: chr9-139981541;