chr19-43733627-C-T

Variant names:

• chr19-43733627-C-T
• NM_019108.4:c.1209G>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Moderate BP6 BP7

The NM_019108.4(SMG9):​c.1209G>A​(p.Lys403Lys) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,816 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: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: SMG9 NM_019108.4 splice_region, synonymous
• Scores: Splicing: ADA: 0.2008
• Clinical Significance: Likely benign no assertion criteria provided B:1
• Conservation: PhyloP100: 2.18
• Publications: 0 publications found

Genes affected

SMG9 (HGNC:25763): (SMG9 nonsense mediated mRNA decay factor) This gene encodes a regulatory subunit of the SMG1 complex, which plays a critical role in nonsense-mediated mRNA decay (NMD). Binding of the encoded protein to the SMG1 complex kinase scaffold protein results in the inhibition of its kinase activity. Mutations in this gene cause a multiple congenital anomaly syndrome in human patients, characterized by brain malformation, congenital heart disease and other features. [provided by RefSeq, Jul 2016]

SMG9 Gene-Disease associations (from GenCC):

• heart and brain malformation syndrome

  Inheritance: AR Classification: STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.21).
• BP6: Variant 19-43733627-C-T is Benign according to our data. Variant chr19-43733627-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 3046450.Status of the report is no_assertion_criteria_provided, 0 stars.
• BP7: Synonymous conserved (PhyloP=2.18 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_019108.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SMG9	NM_019108.4	MANE Select	c.1209G>A	p.Lys403Lys	splice_region synonymous	Exon 11 of 14	NP_061981.2	Q9H0W8-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SMG9	ENST00000270066.11	TSL:1 MANE Select	c.1209G>A	p.Lys403Lys	splice_region synonymous	Exon 11 of 14	ENSP00000270066.6	Q9H0W8-1
	SMG9	ENST00000892518.1		c.1302G>A	p.Lys434Lys	splice_region synonymous	Exon 11 of 14	ENSP00000562577.1
	SMG9	ENST00000892519.1		c.1275G>A	p.Lys425Lys	splice_region synonymous	Exon 11 of 14	ENSP00000562578.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461816 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727206

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111950

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Likely benign

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
-	-	1	SMG9-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.21
CADD	Benign	13
DANN	Benign	0.93
PhyloP100		2.2

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.20
dbscSNV1_RF	Benign	0.18
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

hg19: chr19-44237779;