Holmes C, Russ C, Kirov G, Aitchison K J, Powell J F, Collier D A, Lovestone S
Department of Neurosciences, Institute of Psychiatry, London, United Kingdom.
Biol Psychiatry. 1998 Feb 1;43(3):159-64. doi: 10.1016/S0006-3223(97)00326-0.
The apolipoprotein E (ApoE) epsilon 4 and epsilon 2 alleles may influence the age of onset of depressive illness. Depressive illness of late onset is also a risk factor for Alzheimer's disease (AD), and there is some evidence that the ApoE epsilon 2 allele is associated with depressive symptomatology in AD. Depressive symptomatology in AD may thus share common genetic risk factors with late-onset depressive illness.
The frequency of the epsilon 2 and epsilon 4 alleles of ApoE and their effects on age of onset of disease in three independent groups of subjects, with depressive illness, with AD, and controls, were compared in a defined population from Southeast London.
The frequency of the ApoE epsilon 2 allele was significantly lower in the depressive illness group compared with the control group and was associated with a later mean age at onset. Subjects with depressive symptomatology in AD had a higher frequency of the ApoE epsilon 2 allele and had a significantly later age of onset of depressive illness compared with the nondepressed AD group.
The presence of the ApoE epsilon 2 allele in AD is found to be highly associated with depressive symptomatology, and it is proposed that this subgroup represents the presence of delayed depressive illness and that there are common genetic risk factors between AD and depressive illness.
载脂蛋白E（ApoE）ε4和ε2等位基因可能影响抑郁症的发病年龄。晚发性抑郁症也是阿尔茨海默病（AD）的一个危险因素，并且有一些证据表明ApoE ε2等位基因与AD中的抑郁症状相关。因此，AD中的抑郁症状可能与晚发性抑郁症有共同的遗传危险因素。
在伦敦东南部的一个特定人群中，比较了ApoE的ε2和ε4等位基因在三组独立受试者（患有抑郁症、患有AD和对照组）中的频率及其对疾病发病年龄的影响。
与对照组相比，抑郁症组中ApoE ε2等位基因的频率显著降低，并且与发病时的平均年龄较晚相关。与未患抑郁症的AD组相比，患有AD且有抑郁症状的受试者中ApoE ε2等位基因的频率更高，且抑郁症发病年龄显著更晚。
发现AD中ApoE ε2等位基因的存在与抑郁症状高度相关，并且提出该亚组代表延迟性抑郁症的存在，以及AD和抑郁症之间存在共同的遗传危险因素。
