NM_000155.4:c.779_790delATGTGCGGCGGC

Variant names:

• chr9-34648848-TCGGCATGTGCGG-T
• rs111033762
• NM_000155.4:c.779_790delATGTGCGGCGGC

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM1 PM4 PP3

The NM_000155.4(GALT):​c.779_790delATGTGCGGCGGC​(p.His260_Arg263del) variant causes a disruptive inframe deletion change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type DEL_BIG, and the frequency of such variant types in population databases may be underestimated and unreliable. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: GALT NM_000155.4 disruptive_inframe_deletion
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: 9.15
• Publications: 1 publications found

Genes affected

GALT (HGNC:4135): (galactose-1-phosphate uridylyltransferase) Galactose-1-phosphate uridyl transferase (GALT) catalyzes the second step of the Leloir pathway of galactose metabolism, namely the conversion of UDP-glucose + galactose-1-phosphate to glucose-1-phosphate + UDP-galactose. The absence of this enzyme results in classic galactosemia in humans and can be fatal in the newborn period if lactose is not removed from the diet. The pathophysiology of galactosemia has not been clearly defined. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Apr 2012]

GALT Gene-Disease associations (from GenCC):

• classic galactosemia

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Orphanet
• galactosemia

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen, Myriad Women’s Health

ENSG00000258728 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_000155.4
• PM4: Nonframeshift variant in NON repetitive region in NM_000155.4.
• PP3: No computational evidence supports a deleterious effect, but strongly conserved according to phyloP

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000155.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GALT	NM_000155.4	MANE Select	c.779_790delATGTGCGGCGGC	p.His260_Arg263del	disruptive_inframe_deletion	Exon 8 of 11	NP_000146.2
	GALT	NM_001258332.2		c.452_463delATGTGCGGCGGC	p.His151_Arg154del	disruptive_inframe_deletion	Exon 6 of 9	NP_001245261.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GALT	ENST00000378842.8	TSL:1 MANE Select	c.779_790delATGTGCGGCGGC	p.His260_Arg263del	disruptive_inframe_deletion	Exon 8 of 11	ENSP00000368119.4
	ENSG00000258728	ENST00000556278.1	TSL:5	c.432+397_432+408delATGTGCGGCGGC		intron	N/A	ENSP00000451792.1
	GALT	ENST00000450095.6	TSL:2	c.452_463delATGTGCGGCGGC	p.His151_Arg154del	disruptive_inframe_deletion	Exon 6 of 9	ENSP00000401956.2

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Galactosemia (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		9.2
Mutation Taster		=7/193	disease causing

Splicing

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

Other links and lift over

dbSNP: rs111033762; hg19: chr9-34648845;