Inherited Disorders
Genomic diagnostics provides a comprehensive range of tests for commonly encountered inherited conditions such as coeliac disease, haemochromatosis, thalassaemia and others.
Tests for inherited disorders are used to detect familial genetic variations that are associated with conditions which may manifest in childhood or in adult life. Some conditions are common and seen frequently in general practice, and others may be rarer, with management or diagnosis requiring specialist input. The genetic basis of many conditions is increasingly known, and with this, a growing number of genetic tests are available in their investigation.
If you cannot find information about a test you are interested in on our website, please contact us and we are happy to advise on test appropriateness, availability, and costs.
Familial hypercholesterolaemia (FH) is characterised by very high levels of LDL cholesterol, leading to an increased risk of coronary heart disease (CHD) at an early age. Early and aggressive treatment with high doses of potent statins or statin combination therapy to lower LDL cholesterol significantly reduces CHD morbidity and mortality for people with FH.
Test Name | Familial Hypercholesterolaemia (FH) |
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Clinical Indication | In the investigation of individuals with very high levels of LDL |
Gene(s) | LDLR, PCSK9, APOB, ABCG5, ABCG8, APOE, CYP27A1, LDLRAP1 and LIPA. |
Method | Massively parallel sequencing plus MLPA for LDLR |
Turn around time | 4 – 6 weeks |
Medicare Eligibility | 73352 |
Sample Type | Blood |
Collection Type | 5mL EDTA tube |
Special Instructions | None |
Test Name | Familial test (for FH) |
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Clinical Indication | For patients with a first- or second- degree relative with a confirmed FH-causing pathogenic variant, to determine the presence of that variant in the patient. |
Gene(s) | LDLR, PCSK9, APOB, ABCG5, ABCG8, APOE, CYP27A1, LDLRAP1 or LIPA. |
Method | Massively parallel sequencing |
Turn around time | 2 – 3 weeks |
Medicare Eligibility | 73353 |
Sample Type | Blood |
Collection Type | 5mL EDTA tube |
Special Instructions | None |
Almost all patients affected by coeliac disease have specific variants of the human leucocyte antigens DQ2 and DQ8.These variants have a strong negative predictive value for diagnosis.
Test Name | Coeliac Disease Susceptibility – HLA-DQ2/DQ8 Genotype |
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Clinical Indication | 1. In the investigation of suspected gluten intolerance/coeliac disease or, 2. For risk assessment of a relative of a person with a known coeliac risk genotype |
Gene(s) | HLA-DQ2 & HLA-DQ8 |
Method | Luminex Bead Assay |
Turn around time | 14 days |
Medicare Eligibility | 71151 |
Sample Type | Blood |
Collection Type | 10mL EDTA tube |
Special Instructions | None |
Factor V and Prothrombin are proteins involved in coagulation. A common variant in the Factor V gene and a common variant in the Prothrombin gene have both been implicated in an increased risk of thrombosis.
Test Name | Factor V Leiden, prothrombin G20210A mutation |
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Clinical Indication | For the investigation of: 1. Proven venous thrombosis or pulmonary embolism, or (73308) 2. In a first degree relatives of a patient with a known mutation (73311) |
Gene(s) | F5/F2 |
Method | PCR Genotyping |
Turn around time | 10 days |
Medicare Eligibility | 73308, 73311 – criteria apply |
Sample Type | Blood |
Collection Type | 10mL EDTA tube |
Special Instructions | None |
Hereditary haemochromatosis is a common inherited disorder in which excessive iron is absorbed. Genetic predisposition leads to disease in some but not all cases.
Test Name | Haemochromatosis Genotype |
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Clinical Indication | 1. The investigation of repeatedly elevated transferrin saturation or ferritin levels, 2. The differential diagnosis of a patient with symptoms suggestive of hereditary haemochromatosis, in whom persistent elevation of plasma iron has been proven, 3. Hereditary haemochromatosis risk assessment of a first degree relative of a person with a known HFE gene mutation. |
Gene(s) | HFE (C282Y, H63D and S65C variants only) |
Method | PCR Genotyping |
Turn around time | 1 week |
Medicare Eligibility | 73317 – criteria apply |
Sample Type | Blood |
Collection Type | 10mL EDTA tube |
Special Instructions | None |
The MTHFR gene produces the enzyme methylenetetrahydrofolate reductase (MTHFR). Studies have reported associations of MTHFR polymorphisms with many conditions including autism, schizophrenia, coronary artery disease, foetal neural tube defects, poor pregnancy outcomes and colorectal cancer.
Test Name | MTHFR (Methyl Tetrahydrofolate Reductase) Genotype |
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Clinical Indication | For the investigation of hyperhomocystinaemia |
Gene(s) | MTHFR |
Method | PCR Genotyping |
Turn around time | 2 weeks |
Medicare Eligibility | 73308 – criteria apply |
Sample Type | Blood |
Collection Type | 10mL EDTA tube |
Special Instructions | None |
HLA-B27 is an MHC class I molecule that is associated with a variety of inflammatory conditions.
Test Name | HLA-B27 |
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Clinical Indication | For the investigation of ankylosing spondylitis and certain other immune and autoimmune conditions such as reactive arthritis |
Gene(s) | HLA-B27 |
Method | PCR Genotyping |
Turn around time | 1 week |
Medicare Eligibility | 73320 |
Sample Type | Blood |
Collection Type | 10mL EDTA tube |
Special Instructions | None |
Test Name | Alpha-1 Antitrypsin |
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Clinical Indication |
1. To aid in the diagnosis of the cause of early onset emphysema and/or liver dysfunction 2. To establish the risk of emphysema and/or liver disease due to alpha-1 antitrypsin deficiency 3. To determine the likelihood that children might inherit the risk in parents known to carry an at-risk genotype |
Gene(s) | SERPINA1 |
Method | PCR Genotyping |
Turn around time | 28 days |
Medicare Eligibility | No |
Sample Type | Blood |
Collection Type | 10mL EDTA tube |
Special Instructions | None |
The ApoE gene codes for the protein apoliprotein E. This protein has been implicated in a range of disorders related to lipid metabolism.
Test Name | ApoE Genotyping |
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Clinical Indication | 1. To determine atherosclerosis risk (e4/e4 or e4/e3) 2. To confirm a diagnosis of confirm a diagnosis of type III hyperlipoproteinemia (e2/e2) |
Gene(s) | ApoE (Apolipoprotein E) |
Method | PCR Genotyping |
Turn around time | 28 days |
Medicare Eligibility | No |
Sample Type | Blood |
Collection Type | 10mL EDTA tube |
Special Instructions | None |
Alpha-thalassaemia is a recessive haematological disorder characterised by defects in the production of alpha globin chain of the haemoglobin molecule that decrease normal haemoglobin production with resulting microcytic hypochromic anaemia. The disease typically results from deletions involving the HBA1 and HBA2 genes, though other less frequent mutations can also cause the disorder.
Test Name | Alpha Thalassemia |
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Clinical Indication | To identify the underlying genetic cause in patients with haematological and laboratory evidence of thalassaemia, for diagnostic and reproductive planning purposes. |
Gene(s) | HBA1 and HBA2 for detection of -alpha^3.7, -alpha^4.2, –SEA, –FIL, –THAI, -alpha^20.5 and –MED deletion variants |
Method | Gap PCR, Sanger sequencing and MLPA |
Turn around time | 3 – 4 weeks |
Medicare Eligibility | 73410 , 73411, 73412 – criteria apply to all |
Sample Type | Blood |
Collection Type | 6mL EDTA tube |
Special Instructions | Prior haematological evidence of thalassaemia (e.g. FBC and film including HBH, iron studies, Hb EPG) must be available prior to testing |
Beta Thalassemia is a recessive haematological disorder caused by defects in the production of the beta globin chain of the haemoglobin molecule, caused by mutations in the HBB gene. The severity of the disease depends on variations involved and their presence on one (heterozygous) or both (homozygous) alleles. Other laboratory finding can include microcytic, hypochromic anaemia, and a raised HbA2 on haemoglobin electrophoresis.
Test Name | Beta Thalassemia |
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Clinical Indication | To identify the underlying genetic cause in patients with haematological and laboratory evidence of thalassaemia, for diagnostic and reproductive planning purposes. |
Gene(s) | HBB for sequence variants and 619bp deletion variant |
Method | GAP PCR and Sanger sequencing |
Turn around time | 2 – 4 weeks |
Medicare Eligibility | No |
Sample Type | Blood |
Collection Type | 10mL EDTA tube |
Special Instructions | Prior haematological evidence of thalassaemia (e.g. FBC and film, iron studies, Hb EPG) must be available prior to testing |
Caused by inherited mutations in the FMR1 gene, Fragile X syndrome is the most common cause of familial intellectual disability. This is an X-linked disorder with a complex clinical phenotype.
Test Name | Fragile X |
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Clinical Indication | 1. For the investigation of intellectual disability, developmental delay, autism, late-onset ataxia, neurodegeneration or premature ovarian failure. 2. Risk assessment of a relative of a person with an FMR1 mutation |
Gene(s) | FMR1 |
Method | PCR Fragment Sizing |
Turn around time | 2 weeks |
Medicare Eligibility | 73300 – criteria apply |
Sample Type | Blood |
Collection Type | 10mL EDTA tube |
Special Instructions | None |
Caused by inherited variations in the CFTR gene, depending on their number and type, a variety of clinical outcomes can be observed. These vary from being unaffected to severe lung and pancreatic disorders (CF) or milder effects such as male infertility, bronchiectasis or pancreatitis. This test is included in the Genetic Carrier Screen panel.
Test Name | Cystic Fibrosis | |||
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Clinical Indication | Carrier Screening – Testing of a prospective parent with no family history of cystic fibrosis for determination of the risk of having a child with cystic fibrosis. | Carrier Testing for either: 1. a relative of a person with a known CFTR pathogenic variant 2. a reproductive partner of a person with a known CFTR pathogenic variant | For the testing of a pregnant patient and/or their partner in order to make or exclude a diagnosis of cystic fibrosis in the fetus. | For the investigation of male fertility (CBVAD) |
Gene(s) | CFTR | |||
Method | Allele-specific PCR fragment size analysis | |||
TAT | 2 weeks | |||
Medicare Eligibility | Yes – criteria apply | Yes – criteria apply | ||
Medicare Descriptor | 73451, 73452 | 73348, 73349 | 73350, 73347, 73346 | 73345 |
Sample Type | Blood | |||
Collection Type | 10mL EDTA tube | |||
Special Instructions | None | Must be specialist referred to be MBS-eligible for item numbers 73345, 73346, 73347, 73348 & 73350. |
Gilbert’s syndrome is characterised by jaundice due to increased levels of unconjugated plasma bilirubin. Men are at higher risk than females and usually present post-puberty. In people of northern European ancestry, cases of Gilbert’s syndrome are often associated with inheriting two copies (one from each parent) of a specific mutation in the promoter region of the gene encoding the enzyme glucuronyltransferase (UGT1A1), designated UGT1A1*28 allele. UGT1A1 is a liver enzyme important for clearing conjugated bilirubin from the circulation. In general, other than the low grade elevated bilirubin levels, people with Gilbert’s syndrome exhibit no other signs or symptoms.
Testing for Gilbert’s syndrome may assist in differentiating the cause of isolated elevated bilirubin levels in those patients with normal test results for FBC, reticulocytes, haptoglobin and liver enzymes.
Test Name | Gilbert’s Syndrome Genotyping |
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Clinical Indication | 1. For the investigation of hyperbilirubinaemia (jaundice) 2. To determine greater susceptibility to irinotecan induced gastrointestinal and bone marrow toxicity |
Gene(s) | UGT1A1 (UDP-glucuronosyltransferase Family 1 Member A1) |
Method | PCR Genotyping |
Turn around time | 28 days |
Medicare Eligibility | No |
Sample Type | Blood |
Collection Type | 10mL EDTA tube |
Special Instructions | None |
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