Alpers syndrome (Alpers-Huttenlocher syndrome)

Mitochondrial disorders are clinically heterogeneous and result from dysfunction of the mitochondrial respiratory chain, which can be caused by mutations in mitochondrial DNA (mtDNA) or in nuclear genes. Mitochondrial disorders may affect a single organ, but many involve multiple organ systems particularly those that are highly dependent on aerobic metabolism (brain, skeletal muscle, heart, kidney and endocrine system). Patients may present at any age; however, nuclear DNA mutations generally present in childhood and mtDNA mutations generally present in late childhood or in adults. Some affected individuals exhibit clinical features that fall into a discrete clinical syndrome, such as Leber’s Hereditary Optic Neuropathy (LHON), Kearns-Sayre syndrome (KSS), chronic progressive external ophthalmoplegia (CPEO), mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS), myoclonic epilepsy with ragged-red fibers (MERRF), neurogenic weakness with ataxia and retinitis pigmentosa (NARP) or Leigh syndrome (LS). However, often the clinical features are highly variable and non-specific and many affected persons do not fit into one particular category. Similar clinical features can be caused by mtDNA mutations or nuclear gene mutations. Common features of mitochondrial disease may include ptosis, external ophthalmoplegia, proximal myopathy, exercise intolerance, cardiomyopathy, sensorineural deafness, optic atrophy, pigmentary retinopathy, diabetes mellitus, encephalopathy, seizures, dementia, migraine, stroke-like episodes, ataxia, spasticity, chorea and dementia. Recently, it has been estimated that approximately 7% of patients diagnosed with autism may have an underlying disorder of mitochondrial function .The prevalence of mitochondrial disorders has been estimated 1/5000 to 1/8500 Abnormal amounts of mtDNA, either depletion or amplification (over-replication), can be indicative of mitochondrial dysfunction. Mitochondrial DNA depletion syndrome is a group of mitochondrial disorders characterized by a reduced amount of mitochondrial DNA in tissues. The disorders associated with mtDNA depletion syndrome generally involve neurological symptoms that can occur during infancy or childhood. Symptoms may include muscle weakness, hypotonia, exercise intolerance, developmental delay, lactic acidosis, encephalopathy, hepatopathy, or myopathy. Mitochondrial over-replication can be a cellular response to mitochondrial dysfunction and is characterized by ragged red fibers in the affected muscle specimens of patients with mtDNA mutations in tRNA genes or with large scale mtDNA deletions. Over-replication of mtDNA has also been reported in a later-onset, mild Kearns Sayre syndrome patient with a high heteroplasmy (92%) for a deletion in the mtDNA POLG gene mutations are one of the most common causes of inherited mitochondrial disease. Mutations in the POLG gene cause a spectrum of mitochondrial diseases (see above), with onset ages from the neonatal period to late adult life, including PEO, SANDO, Alpers syndrome, and MNGIE. The clinical presentation ranges from severe encephalopathy and liver failure to late onset external ophthalmoplegia, seizures, ataxia, myopathy and isolated muscle pain. Other findings include cardiomyopathy, cardiac conduction defects, depression, hearing loss, diffuse degeneration of cerebral gray matter, hepatic cirrhosis, and diffuse leukoencephalopathy. Parkinsonism and premature ovarian failure have also been described.Because of the overlap in phenotypes and differences in age of onset, definitive diagnosis of these disorders is dependent upon mutation identification

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Test Details

ADSL, ALDH5A1, ATP1A3, ATRX, CACNA1A, CASK, CDKL5, CHD2, CHRNA2, CHRNA4, CHRNA7, CHRNB2, CLCN4, CLN3, CLN5, CLN6, CLN8, CNTNAP2, CSTB, CTSD, DDX3X, DEPDC5, DYRK1A, EEF1A2, EHMT1, EPM2A, FOLR1, FOXG1, GABRA1, GABRB2, GABRB3, GABRG2, GAMT, GATM, GNAO1, GOSR2, GRIN1, GRIN2A, IQSEC2, KANSL1, KCNA2, KCNC1, KCNMA1, KCNT1, KCTD7, KDM6A, KIAA2022, LGI1, MAGI2, MBD5, MECP2, MEF2C, MFSD8, NALCN, NGLY1, NHLRC1, NPRL3, NRXN1, PACS1, PCDH19, PIGN, PNKP, POLG, PPP2R5D, PPT1, PURA, SCN1A, SCN1B, SCN2A, SLC19A3, SLC2A1, SLC6A1, SLC6A8, SLC9A6, SMC1A, SPATA5, STX1B, SYNGAP1, TBC1D24, TCF4, TPP1, UBE3A, WDR45, ZEB2
  • Molecular confirmation of a clinical diagnosis
  • To assist with decisions about treatment and management of individuals with epilepsy
  • Testing of at-risk relatives for specific known mutation(s) previously identified in an affected family member
  • Prenatal diagnosis for known familial mutation(s) in at-risk pregnancies
  • Next-Gen Sequencing
  • Deletion/Duplication Analysis

Ordering

542
4 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL) | Buccal Swabs

Billing

81404x2, 81405x2, 81406x2, 81407x1
Yes
Yes
* For price inquiries please email zebras@genedx.com

Forms and Documents

Test Details

ADSL, ALDH5A1, ALDH7A1, ALG13, ARHGEF9, ARX, ASNS, ATP1A2, ATP1A3, ATP6AP2, ATRX, BRAT1, CACNA1A, CASK, CDKL5, CHD2, CHRNA2, CHRNA4, CHRNA7, CHRNB2, CLCN4, CLN3, CLN5, CLN6, CLN8, CNTNAP2, CSTB, CTNNB1, CTSD, CTSF, DDX3X, DEPDC5, DNAJC5, DNM1, DYRK1A, EEF1A2, EHMT1, EPM2A, FLNA, FOLR1, FOXG1, FRRS1L, GABBR2, GABRA1, GABRB2, GABRB3, GABRG2, GAMT, GATM, GLDC, GNAO1, GOSR2, GRIN1, GRIN2A, GRIN2B, HNRNPU, IQSEC2, KANSL1, KCNA2, KCNB1, KCNC1, KCNH1, KCNJ10, KCNMA1, KCNQ2, KCNQ3, KCNT1, KCTD7, KDM6A, KIAA2022, LGI1, MAGI2, MBD5, MECP2, MEF2C, MFSD8, NALCN, NGLY1, NHLRC1, NPRL3, NR2F1, NRXN1, PACS1, PCDH19, PIGA, PIGN, PIGO, PIGV, PLCB1, PNKP, PNPO, POLG, PPP2R5D, PPT1, PRRT2, PURA, QARS, SATB2, SCARB2, SCN1A, SCN1B, SCN2A, SCN8A, SLC13A5, SLC19A3, SLC25A22, SLC2A1, SLC6A1, SLC6A8, SLC9A6, SMC1A, SPATA5, SPTAN1, STX1B, STXBP1, SYNGAP1, SZT2, TBC1D24, TBL1XR1, TCF4, TPP1, TSC1, TSC2, UBE3A, WDR45, WWOX, ZEB2
  • Molecular confirmation of a clinical diagnosis
  • To assist with decisions about treatment and management of individuals with epilepsy
  • Testing of at-risk relatives for specific known mutation(s) previously identified in an affected family member
  • Prenatal diagnosis for known familial mutation(s) in at-risk pregnancies
  • Next-Gen Sequencing
  • Deletion/Duplication Analysis

Ordering

523
4 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL) | Buccal Swabs

Billing

81403x1, 81404x5, 81405x2, 81406x2, 81407x1
Yes
Yes
* For price inquiries please email zebras@genedx.com

Forms and Documents

Test Details

AARS2, ABCB7, ACAD9, ACO2, AFG3L2, AGK, AIFM1, ALAS2, APOPT1, ATP5A1, ATP5E, ATP7B, ATPAF2, AUH, BCS1L, BOLA3, C12ORF65, C19orf12, CARS2, CLPB, COA5, COA6, COASY, COQ2, COQ4, COQ6, COQ7, COQ8A, COQ8B, COQ9, COX10, COX14, COX15, COX20, COX6A1, COX6B1, COX8A, CYC1, DARS2, DGUOK, DLAT, DLD, DNA2, DNAJC19, DNM1L, EARS2, ECHS1, ELAC2, ETFA, ETFB, ETFDH, ETHE1, FARS2, FASTKD2, FBXL4, FDX1L, FH, FLAD1, FOXRED1, GARS, GCDH, GFER, GFM1, GFM2, GLRX5, GTPBP3, GYG2, HARS2, HMGCL, HTRA2, IARS2, IBA57, ISCA2, ISCU, LAMP2, LARS, LARS2, LIAS, LIPT1, LRPPRC, LYRM4, LYRM7, MARS2, MFF, MFN2, MGME1, MICU1, MPC1, MPV17, MRPL12, MRPL3, MRPL44, MRPS16, MRPS22, MRPS7, MTFMT, MTO1, MTPAP, NARS2, NDUFA1, NDUFA10, NDUFA11, NDUFA12, NDUFA2, NDUFA4, NDUFA9, NDUFAF1, NDUFAF2, NDUFAF3, NDUFAF4, NDUFAF5, NDUFAF6, NDUFAF7, NDUFB11, NDUFB3, NDUFB9, NDUFS1, NDUFS2, NDUFS3, NDUFS4, NDUFS6, NDUFS7, NDUFS8, NDUFV1, NDUFV2, NFS1, NFU1, NR2F1, NUBPL, OPA1, OPA3, OTC, PARS2, PC, PCCA, PCCB, PDHA1, PDHB, PDHX, PDP1, PDSS1, PDSS2, PET100, PNPT1, POLG, POLG2, PRKAG2, PUS1, QARS, RARS, RARS2, RMND1, RNASEH1, RRM2B, SARS2, SCO1, SCO2, SDHA, SDHAF1, SERAC1, SFXN4, SLC19A2, SLC19A3, SLC22A5, SLC25A26, SLC25A3, SLC25A38, SLC25A4, SLC25A46, SPAST, SPG7, SUCLA2, SUCLG1, SURF1, TACO1, TARS2, TAZ, TFAM, TIMM8A, TK2, TMEM126A, TMEM126B, TMEM70, TPK1, TRIT1, TRMT10C, TRMU, TRNT1, TSFM, TTC19, TUFM, TWNK, TYMP, UQCC2, UQCC3, UQCRB, UQCRC2, UQCRQ, VARS2, WDR45, WFS1, YARS2
  • Molecular confirmation of a clinical diagnosis
  • Testing of patients suspected of having a mitochondrial disorder
  • Prenatal diagnosis for known familial mutation(s) in nuclear genes in at-risk pregnancies.
  • Next-Gen Sequencing
  • Deletion/Duplication Analysis

Ordering

573
6 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL) | Buccal Swabs

Billing

81440x1
Yes
Yes
* For price inquiries please email zebras@genedx.com

References

  1. Oliveira et al. (2005) Dev Med Child Neurol 47 (3):185-9 (PMID: 15739723)
  2. Chinnery P. Mitochondrial Disorders Overview 2000 Jun 8 [Updated 2014 Aug 14]. In: Pagon RA, Adam MP, Ardinger HH, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2018. Available from: https://www.ncbi.nlm.n
  3. Tarnopolsky et al. (2005) Med Sci Sports Exerc 37 (12):2086-93 (PMID: 16331134)
  4. van Adel et al. (2009) Journal Of Clinical Neuromuscular Disease 10 (3):97-121 (PMID: 19258857)
  5. Zhu et al. (2009) Acta Biochim. Biophys. Sin. (Shanghai) 41 (3):179-87 (PMID: 19280056)
  6. Koenig et al. (2008) Pediatr. Neurol. 38 (5):305-13 (PMID: 18410845)
  7. Zeviani et al. (2004) Brain 127 (Pt 10):2153-72 (PMID: 15358637)
  8. Taylor et al. (2014) JAMA 312 (1):68-77 (PMID: 25058219)

Forms and Documents

Test Details

POLG
  • Confirmation of biochemical and clinical diagnosis
  • Carrier testing
  • Prenatal diagnosis when familial mutations are known
  • Capillary Sequencing

Ordering

394
4-5 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL) | Buccal Swabs

Billing

81406x1
No
Yes
* For price inquiries please email zebras@genedx.com

References

  1. McFarland et al., (2008) Arch Dis Child 93:151-153
  2. Horvath et al., (2006) Brain 129:1674-1684
  3. Wong et al., (2008) Hum Mutat 29:E150-E172
  4. Blok et al., (2009, Jul 2) J Med Genet [Epub ahead of print]
  5. Agostino et al., (2003) Neurology 60:1354-1356

Forms and Documents

Test Details

AARS2, ABCB7, ACAD9, ACO2, AFG3L2, AGK, AIFM1, ALAS2, APOPT1, ATP5A1, ATP5E, ATP7B, ATPAF2, AUH, BCS1L, BOLA3, C12ORF65, C19orf12, CARS2, CLPB, COA5, COA6, COASY, COQ2, COQ4, COQ6, COQ7, COQ8A, COQ8B, COQ9, COX10, COX14, COX15, COX20, COX6A1, COX6B1, COX8A, CYC1, DARS2, DGUOK, DLAT, DLD, DNA2, DNAJC19, DNM1L, EARS2, ECHS1, ELAC2, ETFA, ETFB, ETFDH, ETHE1, FARS2, FASTKD2, FBXL4, FDX1L, FH, FLAD1, FOXRED1, GARS, GCDH, GFER, GFM1, GFM2, GLRX5, GTPBP3, GYG2, HARS2, HMGCL, HTRA2, IARS2, IBA57, ISCA2, ISCU, LAMP2, LARS, LARS2, LIAS, LIPT1, LRPPRC, LYRM4, LYRM7, MARS2, MFF, MFN2, MGME1, MICU1, MPC1, MPV17, MRPL12, MRPL3, MRPL44, MRPS16, MRPS22, MRPS7, MTFMT, MTO1, MTPAP, NARS2, NDUFA1, NDUFA10, NDUFA11, NDUFA12, NDUFA2, NDUFA4, NDUFA9, NDUFAF1, NDUFAF2, NDUFAF3, NDUFAF4, NDUFAF5, NDUFAF6, NDUFAF7, NDUFB11, NDUFB3, NDUFB9, NDUFS1, NDUFS2, NDUFS3, NDUFS4, NDUFS6, NDUFS7, NDUFS8, NDUFV1, NDUFV2, NFS1, NFU1, NR2F1, NUBPL, OPA1, OPA3, OTC, PARS2, PC, PCCA, PCCB, PDHA1, PDHB, PDHX, PDP1, PDSS1, PDSS2, PET100, PNPT1, POLG, POLG2, PRKAG2, PUS1, QARS, RARS, RARS2, RMND1, RNASEH1, RRM2B, SARS2, SCO1, SCO2, SDHA, SDHAF1, SERAC1, SFXN4, SLC19A2, SLC19A3, SLC22A5, SLC25A26, SLC25A3, SLC25A38, SLC25A4, SLC25A46, SPAST, SPG7, SUCLA2, SUCLG1, SURF1, TACO1, TARS2, TAZ, TFAM, TIMM8A, TK2, TMEM126A, TMEM126B, TMEM70, TPK1, TRIT1, TRMT10C, TRMU, TRNT1, TSFM, TTC19, TUFM, TWNK, TYMP, UQCC2, UQCC3, UQCRB, UQCRC2, UQCRQ, VARS2, WDR45, WFS1, YARS2
  • Molecular confirmation of a clinical diagnosis
  • Testing of patients suspected of having a mitochondrial disorder
  • Prenatal diagnosis for known familial mutation(s) in nuclear genes in at-risk pregnancies.
  • Next-Gen Sequencing
  • Deletion/Duplication Analysis

Ordering

615
6 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL) | Buccal Swabs

Billing

81460x1, 81465x1, 81440x1
Yes
Yes
* For price inquiries please email zebras@genedx.com

References

  1. Oliveira et al. (2005) Dev Med Child Neurol 47 (3):185-9 (PMID: 15739723)
  2. Chinnery P. Mitochondrial Disorders Overview 2000 Jun 8 [Updated 2014 Aug 14]. In: Pagon RA, Adam MP, Ardinger HH, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2018. Available from: https://www.ncbi.nlm.n
  3. Tarnopolsky et al. (2005) Med Sci Sports Exerc 37 (12):2086-93 (PMID: 16331134)
  4. van Adel et al. (2009) Journal Of Clinical Neuromuscular Disease 10 (3):97-121 (PMID: 19258857)
  5. Zhu et al. (2009) Acta Biochim. Biophys. Sin. (Shanghai) 41 (3):179-87 (PMID: 19280056)
  6. Longo et al. (2003) Neurol Clin 21 (4):817-31 (PMID: 14743651)
  7. Koenig et al. (2008) Pediatr. Neurol. 38 (5):305-13 (PMID: 18410845)
  8. Zeviani et al. (2004) Brain 127 (Pt 10):2153-72 (PMID: 15358637)
  9. Taylor et al. (2014) JAMA 312 (1):68-77 (PMID: 25058219)

Forms and Documents

Test Details

ALDH7A1, ARX, BRAT1, CDKL5, FOLR1, GLDC, KCNQ2, KCNQ3, KCNT1, MECP2, MEF2C, PCDH19, PNPO, POLG, SCN1A, SCN1B, SCN2A, SCN8A, SLC19A3, SLC2A1, SLC6A8, SPTAN1, STXBP1, TPP1, TSC1, TSC2
  • Molecular confirmation of a clinical diagnosis
  • To assist with decisions about treatment and management of individuals with epilepsy
  • Testing of at-risk relatives for specific known mutation(s) previously identified in an affected family member
  • Prenatal diagnosis for known familial mutation(s) in at-risk pregnancies
  • Next-Gen Sequencing
  • Deletion/Duplication Analysis

Ordering

814
2 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL) | Buccal Swabs

Billing

81404x2, 81405x2, 81406x2, 81407x1
Yes
Yes
* For price inquiries please email zebras@genedx.com

Forms and Documents

Test Details

  • Molecular confirmation of a clinical diagnosis
  • To assist with decisions about treatment and management of individuals with epilepsy
  • Testing of at-risk relatives for specific known variant(s) previously identified in an affected family member
  • Prenatal diagnosis for known familial pathogenic variant(s) in at-risk pregnancies
  • Next-Gen Sequencing

Ordering

921
6 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL) | Buccal Swabs

Billing

81404x4, 81405x2, 81406x2, 81407x1, 81408x2, 81302x1
Yes
Yes
* For price inquiries please email zebras@genedx.com

References

  1. Pong et al. (2011) Pediatric Neurology 44 (5):317-27 (PMID: 21481738)
  2. Dyment et al. (2014) Clinical Genetics : (PMID: 25046240)
  3. Michaud et al. (2014) Human Molecular Genetics 23 (18):4846-58 (PMID: 24781210)
  4. Veeramah et al. (2013) Epilepsia 54 (7):1270-81 (PMID: 23647072)
  5. Allen et al. (2013) Nature 501 (7466):217-21 (PMID: 23934111)
  6. EuroEPINOMICS-RES et al. American Journal Of Human Genetics 95 (4):360-370 (PMID: 25262651)
  7. Lee et al. (2014) Jama 312 (18):1880-7 (PMID: 25326637)
  8. McKnight D, Retterer K, Juusola J, Brandt T, Richard G, and Suchy S, Genetic Testing Strategies for Patients with Epilepsy and Neurodevelopmental Disorders; (Abstract #562). Presented at the 2015 ACMG Annual Clinical Genetics Meeting, March 27, 2015, Salt

Forms and Documents

Test Details

ADSL, ALDH5A1, ALDH7A1, ALG13, ARHGEF9, ARID1B, ARX, ASNS, ATP1A2, ATP1A3, ATP6AP2, ATRX, BRAT1, CACNA1A, CASK, CDKL5, CHD2, CHRNA2, CHRNA4, CHRNA7, CHRNB2, CLCN4, CLN3, CLN5, CLN6, CLN8, CNTNAP2, CREBBP, CSTB, CTNNB1, CTSD, CTSF, DDX3X, DEPDC5, DNAJC5, DYRK1A, EEF1A2, EHMT1, EPM2A, FLNA, FOLR1, FOXG1, FRRS1L, GABBR2, GABRA1, GABRB2, GABRB3, GABRG2, GAMT, GATM, GLDC, GNAO1, GOSR2, GRIN1, GRIN2A, GRIN2B, HNRNPU, IQSEC2, KANSL1, KCNA2, KCNB1, KCNC1, KCNH1, KCNJ10, KCNMA1, KCNQ2, KCNQ3, KCNT1, KCTD7, KDM6A, KIAA2022, LGI1, MAGI2, MBD5, MECP2, MEF2C, MFSD8, NALCN, NGLY1, NHLRC1, NPRL3, NR2F1, NRXN1, OPHN1, PACS1, PCDH19, PHF6, PIGA, PIGN, PIGO, PIGV, PLCB1, PNKP, PNPO, POLG, PPP2R5D, PPT1, PRICKLE1, PRRT2, PURA, QARS, SATB2, SCARB2, SCN1A, SCN1B, SCN2A, SCN8A, SLC13A5, SLC19A3, SLC25A22, SLC2A1, SLC6A1, SLC6A8, SLC9A6, SMC1A, SPATA5, SPTAN1, STX1B, STXBP1, SYNGAP1, SZT2, TBC1D24, TBL1XR1, TCF4, TPP1, TSC1, TSC2, UBE3A, WDR45, WWOX, ZEB2
  • Molecular confirmation of a clinical diagnosis
  • To assist with decisions about treatment and management of individuals with epilepsy
  • Testing of at-risk relatives for specific known variant(s) previously identified in an affected family member
  • Prenatal diagnosis for known familial pathogenic variant(s) in at-risk pregnancies
  • Deletion/Duplication Analysis

Ordering

953
4 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL) | Buccal Swabs

Billing

81304x1, 81403x1, 81405x3, 81406x2
No
Yes
* For price inquiries please email zebras@genedx.com