rs773081522

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM2PM4PP5_Very_Strong

The NM_000092.5(COL4A4):​c.1323_1340delTGGCTTGCCTGGAGCACC​(p.Gly442_Pro447del) variant causes a disruptive inframe deletion change. The variant allele was found at a frequency of 0.0000248 in 1,613,652 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. P441P) has been classified as Benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000027 ( 0 hom. )

Consequence

COL4A4
NM_000092.5 disruptive_inframe_deletion

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:10

Conservation

PhyloP100: 6.31
Variant links:
Genes affected
COL4A4 (HGNC:2206): (collagen type IV alpha 4 chain) This gene encodes one of the six subunits of type IV collagen, the major structural component of basement membranes. This particular collagen IV subunit, however, is only found in a subset of basement membranes. Like the other members of the type IV collagen gene family, this gene is organized in a head-to-head conformation with another type IV collagen gene so that each gene pair shares a common promoter. Mutations in this gene are associated with type II autosomal recessive Alport syndrome (hereditary glomerulonephropathy) and with familial benign hematuria (thin basement membrane disease). Two transcripts, differing only in their transcription start sites, have been identified for this gene and, as is common for collagen genes, multiple polyadenylation sites are found in the 3' UTR. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 12 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM4
Nonframeshift variant in NON repetitive region in NM_000092.5.
PP5
Variant 2-227094153-TGGTGCTCCAGGCAAGCCA-T is Pathogenic according to our data. Variant chr2-227094153-TGGTGCTCCAGGCAAGCCA-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 552183.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-227094153-TGGTGCTCCAGGCAAGCCA-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
COL4A4NM_000092.5 linkc.1323_1340delTGGCTTGCCTGGAGCACC p.Gly442_Pro447del disruptive_inframe_deletion 20/48 ENST00000396625.5 NP_000083.3 P53420

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
COL4A4ENST00000396625.5 linkc.1323_1340delTGGCTTGCCTGGAGCACC p.Gly442_Pro447del disruptive_inframe_deletion 20/485 NM_000092.5 ENSP00000379866.3 P53420

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152218
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000404
AC:
10
AN:
247640
Hom.:
0
AF XY:
0.0000223
AC XY:
3
AN XY:
134582
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000279
Gnomad SAS exome
AF:
0.0000656
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000268
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000267
AC:
39
AN:
1461434
Hom.:
0
AF XY:
0.0000344
AC XY:
25
AN XY:
727052
show subpopulations
Gnomad4 AFR exome
AF:
0.0000598
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.000101
Gnomad4 SAS exome
AF:
0.000128
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000180
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152218
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74364
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000151

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:10
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal recessive Alport syndrome Pathogenic:4
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpAug 15, 2024Variant summary: COL4A4 c.1323_1340del18 (p.Pro444_Leu449del) results in an in-frame deletion that is predicted to remove 6 amino acids within the triple-helical region (UniProt) of the encoded protein sequence. This variant disrupts critical glycine residues at position 1 of a Gly-X-Y repeat in the collagenous domain of the collagen IV alpha 4 chain, and variants affecting these glycine residues are significantly enriched in individuals with Alport syndrome (PMID: 33854215). The variant allele was found at a frequency of 4e-05 in 247640 control chromosomes. This frequency is not significantly higher than estimated for a pathogenic variant in COL4A4 causing Alport Syndrome, Autosomal Recessive (4e-05 vs 0.0011), allowing no conclusion about variant significance. c.1323_1340del18 has been reported in the literature in multiple individuals, including compound heterozygotes, homozygotes, and heterozygotes, affected with Alport Syndrome (e.g., Zhu_2018, Boye_1998, Domingo-Gallego_2022, Furlano_2021). These studies have shown segregation of the variant with disease among family members and suggest the variant is associated with both autosomal recessive and dominant forms of disease. These data indicate that the variant is very likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 38317457, 9792860, 33532864, 30745910). ClinVar contains an entry for this variant (Variation ID: 552183). Based on the evidence outlined above, the variant was classified as pathogenic. -
Likely pathogenic, criteria provided, single submitterclinical testingCounsylMay 26, 2017- -
Likely pathogenic, criteria provided, single submitterresearchMolecular Biology Laboratory, Fundació PuigvertFeb 01, 2020- -
Pathogenic, criteria provided, single submitterclinical testing3billionJan 03, 2022This inframe deletion in the non-repeat region can change the length of the protein and disrupt protein function (PM4_M). The variant has been observed in at least two similarly affected unrelated individuals (PMID: 27281700, PMID: 30745910, PMID:9792860, PS4_M). The variant has been reported at least twice as pathogenic/likely pathogenic with clinical assertions and evidence for the classification (ClinVar ID: VCV000552183, 3billion dataset). It is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: 0.000040, PM2_M). he variant has been reported to be in trans with a pathogenic variant as either compound heterozygous or homozygous in at least one similarly affected unrelated individual (PMID: 30745910, PM3_M). Therefore, this variant is classified as pathogenic according to the recommendation of ACMG/AMP guideline. -
not provided Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpOct 05, 2023This variant, c.1323_1340del, results in the deletion of 6 amino acid(s) of the COL4A4 protein (p.Pro444_Leu449del), but otherwise preserves the integrity of the reading frame. This variant is present in population databases (rs773081522, gnomAD 0.03%). This variant has been observed in individual(s) with autosomal recessive and autosomal dominant Alport syndrome (PMID: 9792860, 25307543, 27281700, 30745910). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. This variant is also known as 1527del18bp. ClinVar contains an entry for this variant (Variation ID: 552183). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitterclinical testingMayo Clinic Laboratories, Mayo ClinicJun 23, 2023PP1, PM2_supporting, PM3, PM4, PS4 -
Alport syndrome Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingMolecular Genetics, Royal Melbourne HospitalMar 30, 2023This sequence change is predicted to cause a change in the length of the protein due to an in-frame deletion of six amino acids in a non-repeat region of the COL4A4 protein (p.(Pro444_Leu449del)). The region deleted is highly conserved (100 vertebrates, UCSC), and includes two glycines in Gly-X-Y repeats in the collagenous domain. The highest population minor allele frequency in gnomAD v2.1 is 0.03% (5/17,922 alleles, 0 homozygotes) in the East Asian population, which is consistent with a recessive condition. This variant has been reported in at least two probands autosomal dominant Alport syndrome (PMID: 25307543, 27281700). The variant has been reported to segregate with both dominant and recessive Alport syndrome in 11 affected family members from a single multi-generational family (PMID: 9792860). This variant has been detected in at least three individuals with Alport syndrome. Of those individuals, one individual was homozygous and two were compound heterozygous for the variant and a pathogenic variant confirmed in trans by parental testing (PMID: 9792860, 30745910, 33532864). Based on the classification scheme RMH Modified ACMG Guidelines v1.4.0, this variant is classified as PATHOGENIC. Following criteria are met: PM3_Strong, PP1_Strong, PM4, PM2_Supporting. -
Pathogenic, criteria provided, single submitterclinical testingVictorian Clinical Genetics Services, Murdoch Childrens Research InstituteJul 17, 2023Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0103 - Loss of function is a known mechanism of disease for this gene and is associated with Alport syndrome. Dominant negative is a suspected mechanism of disease for this gene as it is a structural protein (PMIDs: 12028435, 24046192). (I) 0108 - This gene is associated with both recessive and dominant disease. Alport syndrome typically has biallelic inheritance, although rare cases of monoallelic inheritance have been reported (PMID: 28704582). Thin basement membrane nephropathy (TBMN) and focal segmental glomerulosclerosis (FSGS) are associated with autosomal dominant inheritance (OMIM, PMIDs: 16467446, 17942953). (I) 0216 - In-frame deletion in a non-repetitive region that has low conservation. (SP) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD <0.01 for a condition (v2: 10 heterozygotes, 0 homozygotes). (SP) 0601 - Variant is located in the well-established functional Gly-X-Y motif in the collagen triple helical domain (DECIPHER). (SP) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. This variant has been classified as pathogenic and likely pathogenic by clinical laboratories in ClinVar and observed in multiple individuals with either autosomal dominant or autosomal recessive Alport syndrome (PMIDs: 27281700, 28704582, 30745910). (SP) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -
Benign familial hematuria;C4746745:Autosomal recessive Alport syndrome Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsDec 21, 2021- -
Benign familial hematuria Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingEurofins-BiomnisNov 03, 2022- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

Splicing

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.

Other links and lift over

dbSNP: rs773081522; hg19: chr2-227958869; API