Finger dermatoglyphics of 446 male and 463 female Faroe Islanders are described. According to birthplace information for their grandparents the individuals sampled are considered to be representative of all regions of the Faroes. Pattern frequencies are given for individual digits and the tables contain mean radial, ulnar, and unilateral maximal ridge counts. Overall frequencies of patterns and mean total ridge counts in both sexes are compared with other populations in northwestern Europe, several of which have had close historical connections with the Faroes. The Faroese have exceptionally high frequencies of arch and ulnar loop patterns, making their mean pattern intensity index values among the lowest in Europe. Low mean total ridge counts are also characteristic of this population. Icelanders show closer dermatoglyphic resemblance to the Faroese than any other European populations. Low mean total ridge counts among Shetland and Orkney Islanders are noteworthy, and it is possible that the resemblance between these North Atlantic island populations is due to common ancestry arising from Viking settlement during the 8th and 9th centuries. The operation of random genetic drift on the gene pool of the Faroe Islanders is another factor to be considered when assessing their biological affinities.
A sample of the Russian population from the European part of the Russian Federation was examined for the elucidation of the relationship between finger dermatoglyphic characters and general personality traits. Special attention was given to the evaluation of dermatoglyphic phenotype of subjects in consanguineous relation with the person being identified, to anatomic localization of papillar lines and other dermatoglyphic structures of the integrated dermatoglyphic phenotype. The informative value of local dermatoglyphic characters and their combinations was assessed. Methods were proposed for the determination of common personality traits referring persons to a given kinship circle and for the reconstruction of a definite dermatoglyphic milieu.
Prenatal steroid levels, estimated as the ratio of second-to-fourth digit length (2D:4D), have been related to reproductive success in women, but direct associations between 2D:4D and physiological measures of fertility remain rare. A recent study reported that lower, masculinized right hand 2D:4D was correlated with delayed age at menarche in women. We addressed this question by investigating whether 2D:4D was associated with recalled age at menarche in 282 post-reproductive Finnish women, using Cox regression model that controlled for a woman's sibling composition, urban or rural residence and temporal trend in menarcheal age. We found no evidence that neither the 2D:4D of the right nor the left hand were related to a woman's age at menarche among these Finnish women.
The low ratio of second-to-fourth digit length (2D:4D) of parents, a putative indicator of high prenatal and even adult testosterone levels, has been suggested to predict a male-biased secondary offspring sex ratio. We investigated this question in 244 contemporary postreproductive Finnish women. Information on the lifetime offspring birth sex ratio of women was collected by questionnaires and the 2D:4D of both their hands were measured from scanned photographs. We found no evidence that the right hand 2D:4D, the left hand 2D:4D, the mean of the right and the left hand 2D:4D, or the difference between the right and the left hand 2D:4D was related to offspring sex ratio at birth among these women. Our results thus do not support the suggestion that offspring birth sex ratio is related to 2D:4D in women.
Qualitative finger and palmar dermatoglyphics of 547 individuals (293 males, 254 females) belonging to the Chuvashian population of Russia were studied to determine sexual dimorphism. The pattern types are not uniformly distributed on 10 fingers. Sex difference is homogeneous in all fingers whereas palmar patterns reflect the better sex variations for three palmar configurational areas (II, III, and IV). This is perhaps due to embryological development, having a relatively longer growth period compared with fingers (Cummins 1929). The present results of the Chuvashian population are not similar to the results of the five Indian populations of our previous study (Karmakar et al. 2002), perhaps due to a major ethnic difference.
The 2D:4D digit ratio, the relative lengths of the index and ring fingers in humans, is a widely used proxy measure for prenatal testosterone exposure. Varying distributions of androgen and estrogen receptors on the second and fourth digits, both of which regulate digit development, appears to be the basis for this effect. Polymorphism in a tandem repeat in the gene coding for the estrogen receptor a (ESR1) in zebra finches (Taeniopygia guttata) not only explains a significant amount of variation in digit ratio but also seems to explain the significant correlation between digit ratio and sexual behavior in these birds. Here, we investigate the effect of TA polymorphism in ESR1 on 2D:4D and aggressive behavior in men.
We genotyped ESR1 polymorphism in samples collected for a previous study in which we had demonstrated an association between androgen receptor polymorphism and aggression, but not 2D:4D.
We found a significant effect of ESR1 TA repeat number on left hand 2D:4D ratio. More TA repeats were associated with higher, more feminized, digit ratios. We found no effect on right hand 2D:4D. We also found an effect of ESR1 polymorphism on aggressive behavior. Greater heterozygosity in TA(n) was associated with lower physical aggression.
Our results suggest that a significant amount of left hand 2D:4D variation and aggressive behavior is due to this variation in ESR1, and that some of the correlation between digit ratio and social behavior is due to pleiotropic effects of ESR1 variation on the two traits.
The aim of this study was to consider digit ratio (2D:4D: a putative marker of prenatal testosterone and estrogen levels) and aggression in a sample of 1,452 children and adolescents (mean age 13.6 years) from five regions of Russia. The 2D:4D was calculated from direct measurements of the fingers, and aggression scores were obtained from completed Buss and Perry (J Pers Soc Psychol 63 (1992) 452-459) aggression questionnaires. The 2D:4D demonstrated significant sexual dimorphism, with lower 2D:4D in boys in all regions. Physical aggression scores were highest in boys, but verbal aggression, anger and hostility were highest in girls. The highest right hand 2D:4D in boys was found in the most northerly population (Central Russia Region). Our data revealed small, but highly significant negative correlations between right 2D:4D, right-left 2D:4D (DR-L ) and self-ratings on physical aggression in boys, but not in girls. These relationships remained after considering Russian ethnics only, and controlling for region. We suggest that the associations may be due to sex differences in prenatal androgen secretion.
Department of Physical Therapy, Recanati School for Community Health Professions, Faculty of Health Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer Sheva 84105, Israel. email@example.com
In a sample of Chuvashians (803 males and 738 females) we evaluated the mean values of index finger to ring finger (2D:4D) ratio, the contributions of phalanges and metacarpals to the 2D:4D ratio, and the symmetry between right and left 2D:4D ratios. Age, sex, anthropometric data and radiographs of both hands were collected. Each hand was visually classified on a radiograph as either Type 1 - index finger was longer than ring finger; Type 2 - equal; or Type 3 - index shorter than the ring finger. The following measurements (1) from the mid-point of the base of the proximal phalanx to the mid-point of the tip of the distal phalanx; and (2) from the mid-point of the base to the mid-point of the tip of the metacarpal were obtained from the index and ring fingers. Visual classification was significantly associated with the measured 2D:4D length ratio. Women had a higher prevalence of Type 1 and Type 2, but lower prevalence of Type 3 ratio in both hands. Men had smaller measured 2D:4D phalangeal, metacarpal and ray (combined) ratios than women. Symmetry between the right and left hand measured 2D:4D ratios were significant in phalangeal (r=0.657, p