Brosch S, Rauffeisen A, Baur M, Michels L, Trefz F K, Pfister M
Sektion für Phoniatrie und Pädaudiologie der Universitäts- Hals-, Nasen-, Ohrenklinik, Schillerstr. 15, 89077, Ulm, Deutschland.
HNO. 2008 Jan;56(1):37-42. doi: 10.1007/s00106-007-1560-6.
Propionic acidemia is caused by a gene defect leading to malfunction of the enzyme propionyl-CoA carboxylase (PCC) and in turn to a pathologic accumulation of propionic acid. Many mutations have been found at the molecular genetic level over the past 20 years, and their implications for the limitation of enzyme activity of PCC in propionic acidemia are discussed.
As an elevated incidence of deafness has been observed in patients with propionic acidemia, the question arises of whether mutations primarily responsible for this disease could also be the underlying cause for a genetic form of deafness.
As well as a standard pure tone audiogram, a pedigree was elaborated and DNA isolated for each family concerned. In one family several subjects displayed mutations of both the PCCA and the PCCB -subunits; these included only one girl whose phenotype was affected, however.
Mutation of the PCCB subunit p.R113X has not previously been mentioned in the literature. According to our present knowledge no connection can be assumed between either of the two mutations and the severe sensorineural hearing loss.
丙酸血症由基因缺陷导致丙酰辅酶A羧化酶（PCC）功能异常，进而引起丙酸病理性蓄积。在过去20年里，分子遗传学水平上发现了许多突变，并讨论了它们对丙酸血症中PCC酶活性受限的影响。
由于在丙酸血症患者中观察到耳聋发病率升高，因此出现了一个问题，即主要导致这种疾病的突变是否也可能是遗传性耳聋的潜在原因。
除了标准纯音听力图外，还为每个相关家庭绘制了家系图谱并分离了DNA。在一个家庭中，几名受试者显示PCCA和PCCB亚基均发生突变；然而，其中只有一名女孩的表型受到影响。
文献中此前未提及PCCB亚基p.R113X的突变。根据我们目前的认知，无法假定这两种突变中的任何一种与严重感音神经性听力损失之间存在关联。
