However, more research and (pre-)clinical testing is needed before the gene therapy is eligible for approval by the FDA as a treatment modality. Epidemiology
Being X-linked, Barth syndrome has been predominantly diagnosed in males (as of July 2009: 120+ males), although by 2012 a female case had been reported.The syndrome is believed to be severely under-reported due to the complexity of (early) diagnosis. Reports on its incidence and prevalence in the international literature vary; around 1 in every 454,000 individuals are thought to suffer from Barth Syndrome. Incidence has been estimated at anywhere between 1:140,000 (South West England, South Wales) and 1:300,000 - 1:400,000 live births (United States). Geographical distribution is homogenous, with patients (and their family members) on every continent (with known cases in, for example, the US, Canada, Europe, Japan, South Africa, Kuwait, and Australia). History
The syndrome was named for Dr. Peter Barth (b. 1932), a Dutch pediatric neurologist, for his research into and the discovery of the syndrome in 1983. He described a pedigree chart, showing that this is an inherited trait and not a communicated (i.e. infectious) disease. See also
3-Methylglutaconic aciduria
noncompaction cardiomyopathy: mutations to the affected genes in Barth syndrome are also present here. References
External links
Barth Syndrome at NINDS
To likely compensate for the cells energy demand, an upregulation of fatty acid β-oxidation and a decreased concentration of certain amino acids that feed anaplerotically into the citrate cycle, such as glutamine (via the fifth site of the citrate cycle), leucine, isoleucine, threonine (all via the sixth site of the citrate cycle) and aspartate (via the 10th site of the citrate cycle), could be detected. In summary, this reduced mitochondrial respiration and glycolytic flux results in impaired mitochondrial flexibility with a large dependence on fatty acid β-oxidation.However, neurons, with the exception of hypothalamic neurons, are not capable of satisfying their large energy demands by degrading fatty acids. It is speculated that an upregulation of β-oxidation also occurs in brain cells due to the hypofunctional mtFASII pathway. The consequence would be an increased risk for hypoxia and oxidative stress, which may contribute to neurological symptoms in the long term. Methylmalonic acid
Methylmalonic acid is formed from the essential amino acids valine, methionine, threonine and isoleucine, from odd-chained fatty acids, from propionate and from cholesterol side chain, on the degradation path into the citrate cycle. In this process, the last intermediate methylmalony-CoA can be converted to methymalonic acid by a deacylase before incorporation at the succinyl-CoA site of the citrate cycle. At this point, the acyl-CoA synthease encoded by ACSF3 could convert the methylmalonic acid back to methylmalonyl-CoA and then feed it to the citrate cycle with the help of the methylmalonyl-CoA mutase and its cofactor vitamin B12.