Unal Mehmet
Department of Dermatology, Faculty of Medicine, Selçuk University, Konya, Turkey.
J Cosmet Dermatol. 2018 Jun;17(3):545-548. doi: 10.1111/jocd.12403. Epub 2017 Aug 29.
Androgenetic alopecia (AGA) is the most common hair loss. The 2D:4D digit ratio refers to the ratio of the length of the second finger to that of the fourth finger and is thought as a marker of prenatal androgen exposure.
There are many studies which have examined the relationship between 2D:4D ratio and some other diseases. In this study, we evaluated the relationship between digit ratio 2D:4D and AGA.
The study group was composed of a male with AGA and healthy controls. The lengths of patients' second and fourth fingers were measured using a digital caliper with a resolution of 0.01 mm. Finger length was measured on the palmar side of the hand from the basal metacarpophalangeal crease. The 2D:4D ratio was obtained by dividing the length of the second finger by the length of the fourth finger.
A total of 99 males who have androgenetic alopecia with a score of grade III or more and 90 controls were included. The mean age of AGA group was 29.72 ± 5.53, and the mean age of control group was 19.63 ± 5.05. The left-hand 2D:4D ratios of AGA group (0.893 ± 0.267) were significantly lower than healthy controls (0.971 ± 0.028). No significant relationships were found between AGA severity, age of onset,and digit ratios.
The left-hand digit ratio 2D:4D is lower in AGA patients, and therefore, left-hand digit ratio 2D:4D can be used as an estimation tool for AGA development in future. There is not any correlation between digit ratio and age of onset. Also, there is no correlation between digit ratio 2D:4D and AGA severity.
雄激素性脱发（AGA）是最常见的脱发类型。2D:4D指的是食指长度与无名指长度之比，被认为是产前雄激素暴露的一个指标。
有许多研究探讨了2D:4D比值与其他一些疾病之间的关系。在本研究中，我们评估了2D:4D指比值与AGA之间的关系。
研究组由患有AGA的男性和健康对照组成。使用分辨率为0.01毫米的数字卡尺测量患者食指和无名指的长度。手指长度是从掌侧掌指关节基部折痕处进行测量的。2D:4D比值通过将食指长度除以无名指长度得出。
共纳入99例雄激素性脱发程度为III级及以上的男性和90例对照。AGA组的平均年龄为29.72±5.53岁，对照组的平均年龄为19.63±5.05岁。AGA组左手的2D:4D比值（0.893±0.267）显著低于健康对照组（0.971±0.028）。未发现AGA严重程度、发病年龄与指比值之间存在显著关系。
AGA患者左手的2D:4D指比值较低，因此，左手2D:4D指比值可作为未来AGA发生发展的一种评估工具。指比值与发病年龄之间无相关性。此外，2D:4D指比值与AGA严重程度之间也无相关性。
