NM_001122955.4:c.1305_1310dupTTCTGC

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 0P and 1B. BP3

The NM_001122955.4(BSCL2):​c.1305_1310dupTTCTGC​(p.Ala437_Pro438insSerAla) variant causes a disruptive inframe insertion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000682 in 1,614,040 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A437A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

BSCL2
NM_001122955.4 disruptive_inframe_insertion

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 0.972

Publications

0 publications found
Variant links:
Genes affected
BSCL2 (HGNC:15832): (BSCL2 lipid droplet biogenesis associated, seipin) This gene encodes the multi-pass transmembrane protein protein seipin. This protein localizes to the endoplasmic reticulum and may be important for lipid droplet morphology. Mutations in this gene have been associated with congenital generalized lipodystrophy type 2 or Berardinelli-Seip syndrome, a rare autosomal recessive disease characterized by a near absence of adipose tissue and severe insulin resistance. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. Naturally occurring read-through transcription occurs between this locus and the neighboring locus HNRNPUL2 (heterogeneous nuclear ribonucleoprotein U-like 2).[provided by RefSeq, Mar 2011]
HNRNPUL2-BSCL2 (HGNC:49189): (HNRNPUL2-BSCL2 readthrough (NMD candidate)) This locus represents naturally occurring read-through transcription between the neighboring HNRNPUL2 (heterogeneous nuclear ribonucleoprotein U-like 2) and BSCL2 (Berardinelli-Seip congenital lipodystrophy 2 (seipin)) genes on chromosome 11. The read-through transcript is a candidate for nonsense-mediated mRNA decay (NMD), and is unlikely to produce a protein product. [provided by RefSeq, Mar 2011]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

BP3
Nonframeshift variant in repetitive region in NM_001122955.4

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BSCL2NM_001122955.4 linkc.1305_1310dupTTCTGC p.Ala437_Pro438insSerAla disruptive_inframe_insertion Exon 11 of 11 ENST00000360796.10 NP_001116427.1 Q96G97-4A0A024R540

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BSCL2ENST00000360796.10 linkc.1305_1310dupTTCTGC p.Ala437_Pro438insSerAla disruptive_inframe_insertion Exon 11 of 11 1 NM_001122955.4 ENSP00000354032.5 Q96G97-4
HNRNPUL2-BSCL2ENST00000403734.2 linkn.*1356_*1361dupTTCTGC non_coding_transcript_exon_variant Exon 24 of 24 2 ENSP00000456010.1 H3BQZ7
HNRNPUL2-BSCL2ENST00000403734.2 linkn.*1356_*1361dupTTCTGC 3_prime_UTR_variant Exon 24 of 24 2 ENSP00000456010.1 H3BQZ7

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152170
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251208
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000881
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000684
AC:
10
AN:
1461870
Hom.:
0
Cov.:
32
AF XY:
0.00000825
AC XY:
6
AN XY:
727230
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000504
AC:
2
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000540
AC:
6
AN:
1111998
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152170
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74322
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
41428
American (AMR)
AF:
0.00
AC:
0
AN:
15266
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5206
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.225
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Charcot-Marie-Tooth disease type 2 Uncertain:1
Oct 17, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant, c.1113_1118dup, results in the insertion of 2 amino acid(s) of the BSCL2 protein (p.Ser372_Ala373dup), but otherwise preserves the integrity of the reading frame. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with BSCL2-related conditions. ClinVar contains an entry for this variant (Variation ID: 646533). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Congenital generalized lipodystrophy type 2;C2931276:Hereditary spastic paraplegia 17;C4014700:Severe neurodegenerative syndrome with lipodystrophy;C5436838:Neuronopathy, distal hereditary motor, type 5C Uncertain:1
Dec 20, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
Apr 30, 2019
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In-frame duplication 2 amino acids in a non-repeat region; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
0.97
Mutation Taster
=76/24
polymorphism

Splicing

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

Publications

Other links and lift over

dbSNP: rs747175358; hg19: chr11-62457917; API