Genetic conditions

X-linked adrenoleukodystrophy (X-ALD) is an X-linked recessive disorder caused by a disruption to the transport and breakdown of fatty acids in the peroxisomes.

• Genetic conditions

Alpha-thalassaemia is considered an autosomal recessive disorder, but inheritance is complex because the alpha globin chain production is controlled by two genes: HBA1 and HBA2. There are two clinically significant forms of alpha-thalassaemia: the more severe type is known as haemoglobin Bart’s hydrops fetalis (Hb Bart’s), or alpha-thalassaemia major; the milder form is called haemoglobin H disease (HbH).

• Genetic conditions

Beta-thalassaemia is an autosomal recessive condition and is caused by a variant of the beta globin gene.

• Genetic conditions

Classical homocystinuria (HCU) is an autosomal recessive disorder caused by a deficiency in cystathionine β-synthase (CBS) that results in a defect in the catabolic pathway of the amino acid methionine.

• Genetic conditions

Congenital adrenal hyperplasia (CAH) is a group of inherited disorders that result in impaired hormone production from the adrenal glands.

• Genetic conditions

Congenital hypothyroidism (CH) occurs because of defects in the pituitary or thyroid gland, or thyroid hormones, resulting in an absent or underdeveloped thyroid gland (dysgenesis), or a thyroid that cannot make thyroid hormone (dyshormonogenesis).

• Genetic conditions

Cystic fibrosis (CF) is an autosomal recessive inherited, multisystem condition that is most commonly associated with early death due to progressive lung disease.

• Genetic conditions

Duchenne muscular dystrophy (DMD) is a disorder characterised by progressive symmetric muscle weakness commencing in the thighs and pelvis, then extending to other muscles of the body.

• Genetic conditions

Familial adenomatous polyposis (FAP) is an autosomal dominant condition, resulting in an extremely high risk of colorectal cancer, together with other characteristic manifestations.

• Genetic conditions

Familial hypercholesterolaemia (FH) is an autosomal dominant disorder characterised by high levels of serum LDL-cholesterol. If untreated, FH can result in premature coronary artery disease.

• Genetic conditions

Familial medullary thyroid cancer (FMTC) is an inherited condition and a subtype of MEN2 (multiple endocrine neoplasia type 2), a hereditary endocrine cancer syndrome. Individuals with FMTC have a high probability of developing medullary thyroid cancer (MTC) with a lower probability (<5%) of developing the other specific endocrine tumours (phaeochromocytoma or parathyroid hyperplasia) usually associated with MEN2.

• Genetic conditions

Phaeochromocytomas and paragangliomas are uncommon tumours that affect between one and eight people per million each year. Approximately one in three patients presenting with phaeochromocytomas and/or paragangliomas have a gene mutation associated with familial paraganglioma syndromes.

• Genetic conditions