Question: What is (are) Dopa-responsive dystonia ?
Answer: Dopa-responsive dystonia (DRD) is an inherited type of dystonia that typically begins during childhood but may begin in adolescence or adulthood. Depending on the specific type of DRD, specific symptoms can vary. Features can range from mild to severe. In most cases, dystonia begins in the lower limbs and spreads to the upper limbs over time. Symptoms may include unusual limb positioning; a lack of coordination when walking or running; sleep problems; and episodes of depression. Affected people also often develop a group of movement abnormalities called parkinsonism. Although movement difficulties usually worsen with age, they often stabilize around age 30. DRD may be caused by mutations in the GCH1, TH or SPR genes, or the cause may be unknown. Depending on the genetic cause, DRD may be inherited in an autosomal dominant (most commonly) or autosomal recessive manner. This form of dystonia is called 'dopa-responsive' dystonia because the symptoms typically improve during treatment with levodopa and carbidopa.
Source: GARD

Question: Is Dopa-responsive dystonia inherited ?
Answer: How is dopa-responsive dystonia inherited? Depending on the genetic cause of dopa-responsive dystonia (DRD), it may be inherited in an autosomal dominant or autosomal recessive manner. When DRD is caused by mutations in the GCH1 gene, it is inherited in an autosomal dominant manner. This means that having a mutation in only one of the 2 copies of the gene is enough to cause signs and symptoms of the disorder. In some cases, an affected person inherits the mutation from an affected parent; other cases result from having a new (de novo) mutation in the gene. When a person with an autosomal dominant condition has children, each child has a 50% (1 in 2) chance to inherit the mutated gene. Some people who inherit a mutated GCH1 gene never develop features of DRD; this phenomenon is known as reduced penetrance. When DRD is caused by mutations in the TH gene, it is inherited in an autosomal recessive manner. This means that a person must have mutations in both of their copies of the gene to be affected. The parents of a person with an autosomal recessive condition usually each carry one copy of the mutated gene and are referred to as carriers. Carriers typically do not have signs or symptoms. When parents who are both carriers of an autosomal recessive condition have children, each child has a 25% (1 in 4) chance to be affected, a 50% chance to be an unaffected carrier like each parent, and a 25% chance to be unaffected and not be a carrier. When DRD is caused by mutations in the SPR gene, it can be inherited in an autosomal recessive or autosomal dominant manner.
Source: GARD