4-3074876-CCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAG-CCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAG

Variant summary

Our verdict is Benign. The variant received -11 ACMG points: 0P and 11B. BP3BP6_ModerateBA1

The NM_001388492.1(HTT):​c.99_110delGCAGCAGCAGCA​(p.Gln34_Gln37del) variant causes a disruptive inframe deletion change. The variant allele was found at a frequency of 0.0427 in 1,356,160 control chromosomes in the GnomAD database, including 2,218 homozygotes. 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 Likely benign (★).

Frequency

Genomes: 𝑓 0.032 ( 108 hom., cov: 0)
Exomes 𝑓: 0.044 ( 2110 hom. )

Consequence

HTT
NM_001388492.1 disruptive_inframe_deletion

Scores

Not classified

Clinical Significance

Likely benign criteria provided, single submitter B:1

Conservation

PhyloP100: 5.65

Publications

6 publications found
Variant links:
Genes affected
HTT (HGNC:4851): (huntingtin) Huntingtin is a disease gene linked to Huntington's disease, a neurodegenerative disorder characterized by loss of striatal neurons. This is thought to be caused by an expanded, unstable trinucleotide repeat in the huntingtin gene, which translates as a polyglutamine repeat in the protein product. A fairly broad range of trinucleotide repeats (9-35) has been identified in normal controls, and repeat numbers in excess of 40 have been described as pathological. The huntingtin locus is large, spanning 180 kb and consisting of 67 exons. The huntingtin gene is widely expressed and is required for normal development. It is expressed as 2 alternatively polyadenylated forms displaying different relative abundance in various fetal and adult tissues. The larger transcript is approximately 13.7 kb and is expressed predominantly in adult and fetal brain whereas the smaller transcript of approximately 10.3 kb is more widely expressed. The genetic defect leading to Huntington's disease may not necessarily eliminate transcription, but may confer a new property on the mRNA or alter the function of the protein. One candidate is the huntingtin-associated protein-1, highly expressed in brain, which has increased affinity for huntingtin protein with expanded polyglutamine repeats. This gene contains an upstream open reading frame in the 5' UTR that inhibits expression of the huntingtin gene product through translational repression. [provided by RefSeq, Jul 2016]
HTT Gene-Disease associations (from GenCC):
  • Huntington disease
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae), Orphanet
  • Lopes-Maciel-Rodan syndrome
    Inheritance: AR Classification: STRONG, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • juvenile Huntington disease
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -11 ACMG points.

BP3
Nonframeshift variant in repetitive region in NM_001388492.1
BP6
Variant 4-3074876-CCAGCAGCAGCAG-C is Benign according to our data. Variant chr4-3074876-CCAGCAGCAGCAG-C is described in ClinVar as [Likely_benign]. Clinvar id is 3910359.Status of the report is criteria_provided_single_submitter, 1 stars.
BA1
GnomAd4 highest subpopulation (AMR) allele frequency at 95% confidence interval = 0.0603 is higher than 0.05.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HTTNM_001388492.1 linkc.99_110delGCAGCAGCAGCA p.Gln34_Gln37del disruptive_inframe_deletion Exon 1 of 67 ENST00000355072.11 NP_001375421.1
HTTNM_002111.8 linkc.99_110delGCAGCAGCAGCA p.Gln34_Gln37del disruptive_inframe_deletion Exon 1 of 67 NP_002102.4 P42858

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HTTENST00000355072.11 linkc.99_110delGCAGCAGCAGCA p.Gln34_Gln37del disruptive_inframe_deletion Exon 1 of 67 1 NM_001388492.1 ENSP00000347184.5 P42858

Frequencies

GnomAD3 genomes
AF:
0.0322
AC:
4242
AN:
131626
Hom.:
105
Cov.:
0
show subpopulations
Gnomad AFR
AF:
0.0188
Gnomad AMI
AF:
0.0163
Gnomad AMR
AF:
0.0635
Gnomad ASJ
AF:
0.0285
Gnomad EAS
AF:
0.0114
Gnomad SAS
AF:
0.0269
Gnomad FIN
AF:
0.0527
Gnomad MID
AF:
0.0485
Gnomad NFE
AF:
0.0323
Gnomad OTH
AF:
0.0463
GnomAD4 exome
AF:
0.0438
AC:
53612
AN:
1224436
Hom.:
2110
AF XY:
0.0428
AC XY:
25979
AN XY:
607438
show subpopulations
African (AFR)
AF:
0.0966
AC:
2482
AN:
25706
American (AMR)
AF:
0.0864
AC:
2604
AN:
30146
Ashkenazi Jewish (ASJ)
AF:
0.0298
AC:
676
AN:
22708
East Asian (EAS)
AF:
0.00908
AC:
264
AN:
29068
South Asian (SAS)
AF:
0.0294
AC:
2119
AN:
72080
European-Finnish (FIN)
AF:
0.0531
AC:
1723
AN:
32470
Middle Eastern (MID)
AF:
0.0341
AC:
129
AN:
3782
European-Non Finnish (NFE)
AF:
0.0434
AC:
41479
AN:
956726
Other (OTH)
AF:
0.0413
AC:
2136
AN:
51750
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.477
Heterozygous variant carriers
0
1876
3752
5627
7503
9379
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
1682
3364
5046
6728
8410
<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:
0.0322
AC:
4246
AN:
131724
Hom.:
108
Cov.:
0
AF XY:
0.0331
AC XY:
2095
AN XY:
63348
show subpopulations
African (AFR)
AF:
0.0189
AC:
669
AN:
35464
American (AMR)
AF:
0.0638
AC:
855
AN:
13398
Ashkenazi Jewish (ASJ)
AF:
0.0285
AC:
91
AN:
3188
East Asian (EAS)
AF:
0.0114
AC:
47
AN:
4124
South Asian (SAS)
AF:
0.0266
AC:
104
AN:
3908
European-Finnish (FIN)
AF:
0.0527
AC:
388
AN:
7360
Middle Eastern (MID)
AF:
0.0437
AC:
11
AN:
252
European-Non Finnish (NFE)
AF:
0.0323
AC:
1986
AN:
61418
Other (OTH)
AF:
0.0452
AC:
82
AN:
1814
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.482
Heterozygous variant carriers
0
165
329
494
658
823
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
48
96
144
192
240
<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:
0.0414
Hom.:
452

ClinVar

Significance: Likely benign
Submissions summary: Benign:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not specified Benign:1
Feb 16, 2025
Laboratory of Genetics, Children's Clinical University Hospital Latvia
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
5.7
Mutation Taster
=194/6
polymorphism

Splicing

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

Publications

Other links and lift over

dbSNP: rs71180116; hg19: chr4-3076603; COSMIC: COSV104422018; COSMIC: COSV104422018; API