chr2-149569885-A-G

Position:

• chr2-149569885-A-G

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BA1

The NM_015702.3(MMADHC):​c.*89T>C variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.999 in 1,123,958 control chromosomes in the GnomAD database, including 561,420 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

• Frequency:
  • Genomes: 𝑓 1.0 (75823 hom., cov: 34)
  • Exomes 𝑓: 1.0 (485597 hom.)
• Consequence: MMADHC NM_015702.3 3_prime_UTR
• Clinical Significance: Benign criteria provided, multiple submitters, no conflicts B:4
• Conservation: PhyloP100: 0.236

Genes affected

MMADHC (HGNC:25221): (metabolism of cobalamin associated D) This gene encodes a mitochondrial protein that is involved in an early step of vitamin B12 metabolism. Vitamin B12 (cobalamin) is essential for normal development and survival in humans. Mutations in this gene cause methylmalonic aciduria and homocystinuria type cblD (MMADHC), a disorder of cobalamin metabolism that is characterized by decreased levels of the coenzymes adenosylcobalamin and methylcobalamin. Pseudogenes have been identified on chromosomes 11 and X.[provided by RefSeq, Nov 2008]

ACMG classification

Verdict is Benign. Variant got -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.84).
• BP6: Variant 2-149569885-A-G is Benign according to our data. Variant chr2-149569885-A-G is described in ClinVar as [Benign]. Clinvar id is 331374.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BA1: GnomAd4 highest subpopulation (EAS) allele frequency at 95% confidence interval = 0.994 is higher than 0.05.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MMADHC	NM_015702.3	c.*89T>C		3_prime_UTR_variant	8/8	ENST00000303319.10	NP_056517.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MMADHC	ENST00000303319.10	c.*89T>C		3_prime_UTR_variant	8/8	1	NM_015702.3	ENSP00000301920	P1
MMADHC	ENST00000422782.2	c.*89T>C		3_prime_UTR_variant	9/9	5		ENSP00000408331
MMADHC	ENST00000428879.5	c.*89T>C		3_prime_UTR_variant	7/7	2		ENSP00000389060	P1

Frequencies

GnomAD3 genomes AF: 0.998 AC: 151882 AN: 152242 Hom.: 75765 Cov.: 34

Gnomad AFR AF: 0.992

Gnomad AMI AF: 1.00

Gnomad AMR AF: 0.999

Gnomad ASJ AF: 1.00

Gnomad EAS AF: 1.00

Gnomad SAS AF: 1.00

Gnomad FIN AF: 1.00

Gnomad MID AF: 0.997

Gnomad NFE AF: 1.00

Gnomad OTH AF: 0.999

GnomAD4 exome AF: 1.00 AC: 971396 AN: 971598 Hom.: 485597 Cov.: 12 AF XY: 1.00 AC XY: 491313 AN XY: 491390

Gnomad4 AFR exome AF: 0.992

Gnomad4 AMR exome AF: 1.00

Gnomad4 ASJ exome AF: 1.00

Gnomad4 EAS exome AF: 1.00

Gnomad4 SAS exome AF: 1.00

Gnomad4 FIN exome AF: 1.00

Gnomad4 NFE exome AF: 1.00

Gnomad4 OTH exome AF: 0.999

GnomAD4 genome AF: 0.998 AC: 151999 AN: 152360 Hom.: 75823 Cov.: 34 AF XY: 0.998 AC XY: 74339 AN XY: 74506

Gnomad4 AFR AF: 0.992

Gnomad4 AMR AF: 0.999

Gnomad4 ASJ AF: 1.00

Gnomad4 EAS AF: 1.00

Gnomad4 SAS AF: 1.00

Gnomad4 FIN AF: 1.00

Gnomad4 NFE AF: 1.00

Gnomad4 OTH AF: 0.999

Alfa AF: 0.999 Hom.: 9260

Bravo AF: 0.997

Asia WGS AF: 1.00 AC: 3475 AN: 3476

ClinVar

Significance: Benign

Submissions summary: Benign:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:2

Benign, criteria provided, single submitter	not provided	Breakthrough Genomics, Breakthrough Genomics	-	- -
Benign, criteria provided, single submitter	clinical testing	GeneDx	Jun 29, 2018	- -

Disorders of Intracellular Cobalamin Metabolism Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Methylmalonic aciduria and homocystinuria type cblD Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.84
CADD	Benign	9.9
DANN	Benign	0.82

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: rs6742604; hg19: chr2-150426399;