Methylmalonic Acidemia (MMAA, MMAB, MCEE, TCblR, Mutase ) Individual Mutation (NAAT) (code 50014) Notice of Assessment

June 2013

DISCLAIMER: This document was originally drafted in French by the Institut national d'excellence en santé et en services sociaux (INESSS), and that version can be consulted at http://www.inesss.qc.ca/fileadmin/doc/INESSS/Analyse_biomedicale/Juin_2013/INESSS_Analyse_9.pdf. It was translated into English by the Canadian Agency for Drugs and Technologies in Health (CADTH) with INESSS’s permission. INESSS assumes no responsibility with regard to the quality or accuracy of the translation. While CADTH has taken care in the translation of the document to ensure it accurately represents the content of the original document, CADTH does not make any guarantee to that effect. CADTH is not responsible for any errors or omissions or injury, loss, or damage arising from or relating to the use (or misuse) of any information, statements, or conclusions contained in or implied by the information in this document, the original document, or in any of the source documentation. 1 GENERAL INFORMATION 1.1 Requestor: CUSM - Montréal General Hospital. 1.2 Application Submitted: August 1, 2012. 1.3 Notice Issued: April 12, 2013.

Note: This notice is based on the scientific and commercial information (submitted by the requestor[s]) and on a complementary review of the literature according to the data available at the time that this test was assessed by INESSS.

2 TECHNOLOGY, COMPANY, AND LICENCE(S) 2.1 Name of the Technology Restriction fragment length polymorphism (RFLP) analysis. 2.2 Brief Description of the Technology RFLP analysis is a technique used for genetic mapping in order to link a genome directly to a conventional genetic marker. RFLP refers to inherited variations in restriction sites that give rise to differences in the length of the fragments produced through cleavage with the appropriate restriction (Lewin, 1997). Such variations among individuals are caused by genetic polymorphism. More specifically, a patient’s DNA is amplified by PCR10 with primers specific to a segment of the MMAA, MMAB, MCEE, TCblR or Mutase genes that may contain the mutation sought. The amplification is validated through agarose gel electrophoresis, followed by digestion for RFLP analysis. The qualitative analysis of the variations in the restriction template is performed on a gel. 2.3 Company or Developer: Not applicable. 2.4 Licence(s): Not applicable. 2.5 Patent, If Any: Not applicable. 2.6 Approval Status (Health Canada, FDA): Does not use licensed commercial kits. 2.7 Weighted Value: 220.0, according to the application (262.0 in the 2012-2013 Index).

10 The polymerase chain reaction or PCR is a nucleic acid amplification test (NAAT).

1 3 CLINICAL INDICATIONS, PRACTICE SETTINGS, AND TESTING PROCEDURES 3.1 Targeted Patient Group Patients with a family history of the mutation of one of these genes (MMAA, MMAB, MCEE, TCblR or Mutase) or patients with negative complementation11 test results, but with persistent methylmalonic acidosis (information submitted by the requestor). 3.2 Targeted Disease(s) (MMA) is a metabolic acidosis characterized by an abnormal accumulation of methylmalonic acid in the blood, in urine12 or in human tissues (Bodamer and Lee, 2011; Fowler et al., 2008). This abnormality may or may not be genetic in nature (Fowler et al., 2008). Genetic causes include methylmalonyl-CoA mutase deficiency, methylmalonyl-CoA epimerase deficiency, defects in cobalamin ( B12) absorption or transport, disorders of intracellular cobalamin and succinate-CoA ligase deficiency. Nutritional deficiencies and a reduction of intestinal absorption (in the elderly) are the main non-genetic causes13. The disease often appears after the early neonatal stage14, during childhood or later in life (Dobson et al., 2002). The clinical consequences are severe and can be fatal: hypotonia15, convulsions, anemia, delayed mental development, digestive or respiratory problems, neurological damage, coma, and death16 (Quadros et al., 2010). The hereditary form is a rare autosomal recessive inherited disease. Various genes may be responsible for this abnormality , namely the MMAA, MMAB, MCEE, TCblR, and Mutase genes. The global prevalence of the disease is less than 1 per 1,000,00017. Incidence is estimated at approximately 1 per 50,000 children worldwide (Fernandes et al., 2006, quoted in AETMIS, 2009) and at 1 per 39,000 in Quebec (Auray-Blais et al., 2007). MMA has been observed in all ethnic groups (Bodamer and Lee, 2011). 3.3 Number of Patients Targeted A total of 103 tests per year (information submitted by the requestor). 3.4 Medical Specialties Involved (and Other Professionals, If Any) Genetics, pediatrics. 3.5 Testing Procedure A clinical laboratory specialist must be consulted before the prescription is written (information submitted by the requestor). The collection of blood samples or skin biopsies (fibroblasts in cell culture) as well as transport and storage conditions comply with the current procedures for this type of biomedical test.

11 A complementation analysis is used in order to determine whether two independent mutations are the result of modifications in a single (i.e., allele) or in different genes (Michels, 2002). 12 The term “aciduria” is used when methylmalonic acid is detected in urine. 13 As part of the present evaluation, emphasis was placed on genetic methylmalonic acidemia. 14 Association québécoise des maladies métaboliques du Réseau (AQMMR). Methylmalonic acidemia (website). Available at: http://www.aqmmr.com/fr/acidemie_methyl.shtml (consulted on March 1, 2013). 15 Hypotonia is a state of low muscle tone. 16 Orphanet. Methylmalonic acidemia (website (research module)). Available at: http://www.orpha.net/consor/cgi- bin/Disease_Search.php?lng=FR. 17 Idem.

2 4 TECHNOLOGY BACKGROUND 4.1 Nature of the Diagnostic Technology Complementary (for diagnostic confirmation). 4.2 Brief Description of the Current Technological Context In Quebec, methylmalonic acidemia is detected under the Quebec Newborn Urine Screening Program for Inborn Errors of Metabolism. An organic acid analysis is performed on urine18 through thin-layer chromatography or through gas chromatography/mass spectrometry (AETMIS, 2009). This screening technique facilitates early treatment initiation. An enzyme activity assay and a complementation test may be performed to make a diagnosis or find the mutation responsible for MMA in order to provide the proper care for patients. When such tests fail, RFLP analysis may help find the mutation responsible for the abnormality detected in known genes. If necessary, sequencing of the genome may be performed, but this option is only available in the United States (information submitted by the requestor). 4.3 Brief Description of the Advantages Cited for the New Technology RFLP analyses are more affordable than complementation tests (weighted average of 262 versus 1,544). Furthermore, they are faster and less costly than genome sequencing. Indeed, the procedure takes 125 minutes (according to the information submitted by the requestor) when analyzing a few specific sites in known gene(s), while sequencing may take several hours (increasing costs). RFLP analyses can also detect MMA carriers, namely in families where the disease is present (information submitted by the requestor). 4.4 Cost of Technology and Options: No analysis conducted.

5 EVIDENCE 5.1 Clinical Relevance 5.1.1 Other Tests Replaced: No. 5.1.2 Diagnostic or Prognostic Value No data are available on the contribution of RFLP analyses in reducing mortality and morbidity or in improving the survival or quality of life in patients with methylmalonic acidemia. Treatments generally consist of diets and supplements: a low-calorie, low- diet supplemented with carnitine or vitamin B12 depending on the particular form of methylmalonic acidemia (Bodamer and Lee, 2011; Manoli and Venditti, 2010). Cases of MMAA mutations do respond to vitamin B12 treatment. In other cases, identification of the mutation is for prognostic purposes. In certain cases, a liver or kidney transplant may be required. These treatments may be initiated based on screening or upon diagnosis after analysis of a series of biomedical tests (enzymatic assay, complementation analysis, etc.). RFLP analyses can confirm the

18 Test administered on the 21st day of age, urine on blotting paper.

3 diagnosis (for a few known mutations only) when the other tests performed are inconclusive and acidosis persists, which in turn allows for treatments to be initiated and thereby prevents metabolic crises. The importance of performing this genetic test for MMA carriers can also be related to family planning, if family history is known. The identification of mutations is important for genetic counselling. 5.1.3 Therapeutic Value No information relative to therapeutic value was found. However, Committee members wish to stress the importance of identifying the mutation, as vitamin B12 treatment is only effective for certain mutations. 5.2 Clinical Validity No information on clinical validity was found. Neither the positive nor the negative predictive value applies, given the rarity of the disease. 5.3 Analytical (or Technical) Validity No information on analytical validity was found. One of the limitations of RFLP analyses pertains to the use of enzymes that generate a known restriction pattern for a given gene. Therefore, the appropriate restriction enzymes are required for the detection of MMA mutations. The other limitations are intrinsic to genetic testing in general. There may be cases of interference during the analysis. These interferences may consist of exogenous substances in the sample, contamination (crossed or not), and quality issues pertaining to samples, control samples, enzymes, or the reagents used. Low-quality DNA preparations may lead to incomplete digestion, thereby distorting results. Without external quality control procedures, laboratories must establish their own internal quality control procedures for mutations in this rare disease.

4 5.4 Recommendations for Listing in Other Jurisdictions No recommendation found.

6 ANTICIPATED OUTCOMES OF INTRODUCING THE TEST 6.1 Impact on Material and Human Resources: Not assessed. 6.2 Economic Consequences of Introducing Test Into Quebec’s Health Care and Social Services System: Not assessed. 6.3 Main Organizational, Ethical, and Other (Social, Legal, Political) Issues RFLP analysis of MMA raises ethical issues regarding screening for rare diseases in carriers with family history of this abnormality and for whom there is no treatment available other than those initially proposed at the time of early testing upstream of the diagnostic series. This analysis may put an end to diagnostic errors when diagnostic test results are negative or inconclusive, despite persistent methylmalonic acidosis.

5 7 INESSS NOTICE IN BRIEF Methylmalonic Acidemia (MMAA, MMAB, MCEE, TCblR, Mutase Genes) Individual Mutation (NAAT) (Code 50014)

Status of the Diagnostic Technology:  Established  Innovative  Experimental (for research purposes only)  Replacement for technology: , which becomes obsolete

INESSS Recommendation:  Keep test in the Index  Remove test from the Index  Reassess test

Additional Recommendation:  Draw connection with listing of drugs, if companion test  Production of an optimal use manual  Identify indicators, when monitoring is required

Note: The requestor and its laboratory have expertise recognized at the international level.

6 REFERENCES Agence d’évaluation des technologies et des modes d’intervention en santé (AETMIS). La pertinence du dépistage néonatal urinaire des erreurs innées du métabolisme réalisé au Québec. Report prepared by Jolianne Renaud and Pierre Dagenais. ETMIS 2009;5(1):1-103. Auray-Blais C, Cyr D, Drouin R. Quebec neonatal mass urinary screening programme: From micromolecules to macromolecules. J Inherit Metab Dis 2007;30(4):515-21. Bodamer OA et Lee B. Genetics of methylmalonic academia (site Web mis à jour le 14 septembre 2011). Medscape Reference; 2011. Available from: http://emedicine.medscape.com/article/947154-overview (Overview); http://emedicine.medscape.com/article/947154-clinical (Presentation); http://emedicine.medscape.com/article/947154-treatment (Treatment). Dobson CM, Wai T, Leclerc D, Wilson A, Wu X, Doré C, et al. Identification of the gene responsible for the cblA complementation group of vitamin B12-responsive methylmalonic acidemia based on analysis of prokaryotic gene arrangements. Proc Natl Acad Sci U S A 2002;99(24):15554-9. Fernandes J, Saudubray JM, Van den Berghe G, Walter JH. Inborn metabolic diseases: Diagnosis and treatment. 4e éd. Heidelberg, Germany: Springer; 2006. Fowler B, Leonard JV, Baumgartner MR. Causes of and diagnostic approach to methylmalonic acidurias. J Inherit Metab Dis 2008;31(3):350-60. Lewin B. Genes VI. New York, NY : Oxford University Press; 1997. Manoli I et Venditti CP. Methylmalonic acidemia (mis à jour le 28 septembre 2010). Dans : Pagon RA, Adam MP, Bird TD, et al., ed. GeneReviews. Seattle, WA : University of Washington; 2010. Available from: http://www.ncbi.nlm.nih.gov/books/NBK1231/. Michels CA. Chapter 5. Complementation analysis: How many genes are involved? Dans : Genetic techniques for biological research: A case study approach. New York, NY : John Wiley and Sons; 2002 : 73-7. Quadros EV, Lai SC, Nakayama Y, Sequeira JM, Hannibal L, Wang S, et al. Positive newborn screen for methylmalonic aciduria identifies the first mutation in TCblR/CD320, the gene for cellular uptake of transcobalamin-bound vitamin B(12). Hum Mutat 2010;31(8):924-9.

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