Marisa Wexler, MS,  senior science writer—

Two previously unknown gene mutations that cause aromatic L-amino acid decarboxylase (AADC) deficiency have been identified in two siblings whose cases were described in a new report. The mutations were found in the DDC gene in the African American sisters. Titled “Case report: discovery of 2…

A range of disease presentations, and of underlying genotypes, were observed in a study of aromatic l-amino acid decarboxylase (AADC) deficiency cases in mainland China. These findings broaden the known clinical signs associated with AADC deficiency, and they hint at connections between genotypes and disease course. The study, “…

Mutations discovered in the past five years that cause aromatic amino acid decarboxylase (AADC) deficiency affect the functioning of the AADC protein in previously unappreciated ways, namely promoting aggregation and preventing interactions among AADC protein pairs, a molecular study demonstrates. The new mechanisms identified in the study light the…

A new technique using dried blood spots could help in the diagnosis of aromatic L-amino-acid decarboxylase (AADC) deficiency and may be especially useful in newborn screening, a study demonstrates. The study, “High throughput newborn screening for aromatic L‐amino‐acid decarboxylase deficiency by analysis of concentrations of 3‐O‐methyldopa…

PTC Therapeutics has launched a program to deliver — at no cost — blood tests that can help diagnose aromatic L-amino acid decarboxylase (AADC) deficiency, the company announced. AADC deficiency, a genetic and neurometabolic disease, is caused by mutations in the gene DDC, which codes for the…

A broad range of diagnostic tools are available for diagnosing AADC deficiency and similar conditions. A recent review paper discusses many of these, highlighting the benefits and pitfalls of those available, and giving a view toward how new diagnostic methods may be applied in the future. The paper, “…

A genetic variant of DDC, the gene encoding L-aromatic amino acid decarboxylase (AADC), contributes to worse somatic symptoms due to low levels of serotonin — a neurotransmitter that contributes to well-being and happiness — in circulation, new research suggests. The study, “A functional substitution…

In a new study, investigators characterized the molecular consequences of two particular variants in the aromatic amino acid or dopa decarboxylase (DDC) gene at the protein level. It is hoped that better understanding such details will lead to better prognoses and, eventually, targeted therapies. The study, “…

A recent report reviewing the use of gene therapy for Taiwanese patients with aromatic l‐amino acid decarboxylase (AADC) deficiency suggests that such strategies may one day lead to a cure for this condition. The report, “A review of aromatic l‐amino acid decarboxylase (AADC) deficiency in Taiwan,” was…

A new study has begun to unravel how heterozygous mutations in aromatic l-amino acid decarboxylase (AADC) deficiency patients affect protein function at the molecular level, providing evidence for a complementary function when the mutations R347Q and R358H both are present. The study, “Heterozygosis in aromatic amino acid decarboxylase…