Mutations Position Table
APP Duplication - Mutations
Mutation | Pathogenicity | DNA Change | Expected RNA | Protein Consequence | Coding/Non-Coding | Genomic Region | Neuropathology | Biological Effect | Primary Papers |
---|---|---|---|---|---|---|---|---|
Duplication 1104 [APP-APP] |
AD : Pathogenic, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | In one carrier, examination of the brain at autopsy revealed neuropathology consistent with AD and CAA. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. This duplication includes a single gene: APP. |
Sleegers et al., 2006 |
Duplication ALZ-254 [POTED-ADAMTS5] (EXT-254 [POTED-ADAMTS5]) |
AD : Not Classified | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Wallon et al., 2012 |
Duplication ALZ-478 [LINC00158-EIF4A1P] |
AD : Pathogenic, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown, but an MRI scan of one carrier revealed probable CAA. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. This duplication includes a single gene: APP. |
Grangeon et al., 2023 |
Duplication [APP-CYYR1] |
AD : Pathogenic | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown, but CT and MRI scans of 4 affected and 6 asymptomatic carriers revealed white matter lesions or some form of vascular alteration. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Kalfon et al., 2022 |
Duplication EXT-006 [HSPA13-GRIK1] |
AD : Not Classified | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. This duplication includes a single gene: APP. |
Grangeon et al., 2023 |
Duplication EXT-019 [LINC00158-USP16] |
AD : Pathogenic, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Consistent with AD and CAA. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. This duplication includes a single gene: APP. |
Grangeon et al., 2023 |
Duplication EXT-054 [USP25-ADAMTS1] |
AD : Pathogenic, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Neuropathology unknown, but MRI of one carrier revealed CAA with 2 intracerebral hemorrhages, 6 cerebral microbleeds, and cortical superficial siderosis. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Wallon et al., 2012 |
Duplication EXT-144 [BTG3-EIF4A1P] |
AD : Pathogenic, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Consistent with severe CAA in 1 carrier and probable CAA detected by MRI in another. Absence of neurofibrillary tangles. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Wallon et al., 2012 |
Duplication EXT-145 [NCAM2-EIF4A1P] |
AD : Not Classified, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown, but MRI of one carrier revealed probable CAA with 3 intracerebral hemorrhages and 13 cerebral microbleeds. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Wallon et al., 2012 |
Duplication EXT-187 [POTED-ADAMTS5] |
AD : Not Classified | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Wallon et al., 2012 |
Duplication EXT-262 [JAM2-APP] (BES-262 [JAM2-APP]) |
AD : Pathogenic, CAA : , DLB : Not Classified | Duplication | Duplication | Duplication | Both | Chromosome 21 | In one carrier, neuropathology was consistent with AD with severe CAA and LBD. CAA and Lewy bodies were widespread. MRI of 3 carriers suggests neuropathology is heterogenous. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Guyant-Marechal et al., 2008 |
Duplication EXT-279 [GABPA-ADAMTS1] |
AD : Not Classified | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Wallon et al., 2012 |
Duplication EXT-298 [GABPA-CYYR1] |
AD : Pathogenic, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Consistent with AD and CAA in one case, and MRI revealed probable CAA in another. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Wallon et al., 2012 |
Duplication EXT-773 [LINC00158-CYYR1] |
AD : Not Classified, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Neuropathology consistent with AD and severe CAA in cortex, insula, and basal ganglia. Also, Lewy bodies in the amygdala, locus niger, nucleus basalis of Meynert, and entorhinal cortex. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Rovelet-Lecrux et al., 2015 |
Duplication EXT-814 [NCAM2-ADAMTS5] |
AD : Not Classified, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown, but CSF biomarkers were consistent with AD and MRI revealed probable CAA in one carrier. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Lanoiselée et al., 2017 |
Duplication EXT-857 [MRPL39-ADAMTS5] |
AD : Pathogenic | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown, but CSF biomarkers were consistent with AD in one carrier. MRI showed no signs of CAA. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Lanoiselée et al., 2017 |
Duplication EXT-1093 [AK124194-CYYR1] |
AD : Not Classified | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown, but CSF biomarkers were consistent with AD in one carrier. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Lanoiselée et al., 2017 |
Duplication EXT-1230 [BTG3- ADAMTS5] |
AD : Not Classified | Duplication | Duplication | Duplication | Both | Unknown. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. This duplication includes a single gene: APP. |
Grangeon et al., 2023 | |
Duplication EXT-1252 [LINC00158-ADAMTS1] |
AD : Not Classified, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown, but CSF biomarkers were consistent with AD in one carrier and MRI showed probable CAA. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood |
Lanoiselée et al., 2017 |
Duplication EXT-1516 [APP-ADAMTS1] |
AD : Not Classified, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown, but MRI of one carrier revealed probable CAA. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. This duplication includes a single gene: APP. |
Grangeon et al., 2023 |
Duplication EXT 1853 [MRPL39-CYYR1] |
AD : Not Classified | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown. In one carrier, MRI revealed no sign of CAA. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. This duplication includes a single gene: APP. |
Grangeon et al., 2023 |
Duplication EXT-1864 [TUBAP-ADAMTS1] |
AD : Not Classified, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown, but MRI of one carrier revealed probable CAA. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. This duplication includes a single gene: APP. |
Grangeon et al., 2023 |
Duplication EXT 2066 [MRPL39-APP] |
AD : Not Classified | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. This duplication includes a single gene: APP. |
Grangeon et al., 2023 |
Duplication F009 [LINC00158-EIF4A1P] |
AD : Pathogenic | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Rovelet-Lecrux et al., 2006 |
Duplication F019 [LINC00158-BACH1] |
AD : Pathogenic, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Neuropathology consistent with AD and severe CAA in two carriers. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Rovelet-Lecrux et al., 2006 |
Duplication F028 [MRPL39-APP] (ALZ-028 [MRPL39-APP]) |
AD : Pathogenic, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Neuropathology was consistent with AD and severe CAA in two carriers. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Rovelet-Lecrux et al., 2006 |
Duplication F037 [LINC00158-APP] (ROU-037 [LINC00158-APP]) |
AD : Pathogenic, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Neuropathology was consistent with AD and severe CAA in 3 carriers. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Rovelet-Lecrux et al., 2006 |
Duplication F229 [NCAM2-EIF4A1P] (ALZ-229 [NCAM2-EIF4A1P]) |
AD : Pathogenic, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown, but hypoperfusion was seen in cortex of 1 carrier and was diffuse in another. MRI showed parieto-occipital and frontal white matter changes in the former. Atrophy was severe in the parieto-temporal cortices of both carriers. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Rovelet-Lecrux et al., 2006 |
Duplication [JAM2-APP] |
AD : Pathogenic, CAA : | Duplication | Duplication | Duplication | Both | Chromosome 21 | Neuropathology consistent with AD and severe CAA in 3 carriers. |
Data unavailable for this specific duplication, but pooled data reveal APP duplications increase APP expression by ~1.5 in blood. |
Rovelet-Lecrux et al., 2007; Remes et al., 2004 |
Duplication PED 2945 [APP-CYYR1] |
AD : Not Classified | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown, but CSF biomarkers were consistent with AD. MRI of one carrier showed mild cortical atrophy without cerebrovascular alterations. |
Levels of APP mRNA in the proband's blood were elevated ~1.5-fold. |
Kasuga et al., 2009 |
Duplication PED 3281 [LINC00158-ADAMTS5] (PED 3281 [C21orf42-ADAMTS5]) |
AD : Not Classified | Duplication | Duplication | Duplication | Both | Chromosome 21 | Unknown, but CSF biomarkers were consistent with AD and brain imaging revealed sucbcortical white matter microbleeds and hyperintensities in one carrier. |
Increased APP mRNA in blood ~1.5-fold. |
Kasuga et al., 2009 |
Triplication [APP-APP] |
AD : Pathogenic, CAA : | Triplication | Triplication | Triplication | Both | Chromosome 21 | CAA observed in a non-genotyped family member. One carrier had brain vascular alterations as revealed by MRI and CSF biomarkers (Aβ42, Aβ40, tau, phospho-tau) consistent with AD. |
APP mRNA levels in blood were increased 2-fold in the proband. |
Grangeon et al., 2021 |
Duplications and triplications of regions at the APP locus are associated with autosomal dominant early onset Alzheimer’s disease (AD), often accompanied by cerebral amyloid angiopathy (CAA). Although varying in size—ranging from 0.5Mb lengths that include only the APP gene to stretches over 14 Mb harboring multiple genes—these amplified regions result in similar phenotypes. Age at onset for AD is usually in the early 50s and carriers often have brain vascular disease, including CAA, intracerebral hemorrhage, and/or microbleeds. Seizures are also a common phenotype. Several lines of evidence point to increased APP expression as the root cause of disease. Also of note, clinical heterogeneity has been observed, not only between carriers of different duplications, but within family members carrying the same mutation. Neighboring genes may act as modifiers, but clear correlations between specific genes and clinical consequences remain uncertain. The duplications, and in one case triplication, appear to result from the APP locus being in a recombination hot spot harboring multiple low-copy repeats. Individuals with Down syndrome, in which the entire chromosome 21, including the APP locus, is duplicated, also develop AD pathology and CAA at an early age.
NOTE: When available, the names of duplications and triplications in this list include the family/patient identifier followed by the genes at the 5' and 3' boundaries of the repeated segments, in brackets.
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