ABSTRACT
Digit ratio (2D:4D) is a sexually dimorphic trait, with females having a higher 2D:4D than males. This digit ratio has been associated with numerous behavioural traits and health conditions related to sex hormones. Four hundred and twelve secondary school students (209 males and 203 females) aged 12 to 20 years attending secondary schools within Enugu metropolis, in Enugu state, Nigeria participated in this work after an informed consent was obtained from them and their parents. Detailed information required from subjects was obtained through a standard designed questionnaire. Body fat percentage, weight (kg), Finger length (cm), height (cm), chest, waist and hip circumferences (cm) were measured using standard protocols. Body mass index (BMI), Waist to chest ratio (WCR) and Waist to hip ratio (WHR) were calculated. Blood sample for the estimation of testosterone was also obtained. The variables were studied according to sex and age groups. The data obtained was subjected to statistical analysis using SigmaStat 2.0 for Windows (San Rafael, CA) and statistical values were acceptable at p<0.05. Testosterone and all the anthropometric variables considered in this studyshowed statistical significant difference (p<0.001 and 0.002) between males and females. The result also indicated a negative significant relationship between 2D:4D of both hands and testosterone in males, while in females testosterone had a positive correlation with 2D:4D of the right hand and a negative correlation 2D:4D of the left hand (p<0.05). 2D:4D of both hands had a negative correlation with weight and height in females (p<0.01 and p<0.05) respectively while in males, 2D:4D did not correlate with height and weight (p>0.05). Males had a significant relationship with weight, height, body fat percentage and chest circumference (p<0.01) while in females testosterone had a significant relationship with weight, body mass index, body fat percentage, waist to hip ratio, chest, waist and hip circumference (p<0.05). In conclusion, the present study confirmed the existence of sexual dimorphism of finger lengths and digit ratios as well as in body composition variables. It also showed a relation between digit ratios and testosterone in the adolescent age group. These findings could be of importance in addressing biological traits and health conditions related to sex hormones.