Fingerprint pattern factors

Factor analysis was employed using the ulnar ridge count, radial ridge count, ridge count (the larger of the radial or ulnar count as generally used for calculating total ridge count), and pattern type for each finger in 720 twins. Pattern type and ulnar count displayed parallel factor loadings while loadings for radial and ridge count also paralleled each other. This relationship did not hold for the index finger, indicating the importance of pattern direction and greater pattern diversity for this digit. Total ridge count was most closely associated with a factor of ring and little finger radial and ridge count and only secondarily with an index finger factor. When radial and ulnar counts were deleted to make comparisons with earlier studies, the result was factors having groupings of variables identical with previous reports. It appears that factor analysis results in consistent extraction of identical or very similar factors from different populations, and the use of radial and ulnar counts adds more information than when only the larger of the two counts is considered.     

Inter-sex and intra-sex differences in quantitative digital dermatoglyphics of Sardinian-speaking groups

In this study, we analysed inter-sex differences within two linguistic groups from the Sardinian linguistic area and intra-sex differences between the two groups by means of 41 quantitative digital dermatoglyphic variables: 20 digital dermatoglyphic traits (radial and ulnar ridge counts on each of the 10 fingers), 15 digital dermatoglyphic directional asymmetry variables, total finger ridge count, bilateral summed radial and ulnar finger ridge counts, an index of asymmetry between homologous fingers, and two indices of intra-individual diversity of finger ridge counts. The comparisons between males and females within the same linguistic groups and between the males of the two groups and the females of the two groups were carried out with the Mann-Whitney test at a prefixed level of alpha = 0.05, using the Bonferroni correction for multiple comparisons. The results indicate a strong similarity of the two linguistic groups in the inter-sex differences, whereas there are no significant differences between them for either males or females. The similar pattern of sexual dimorphism and the homogeneity of the males and females of the two groups suggest a common genetic matrix of these Sardinian-speaking groups.     

Digital dermatoglyphics of 107 Bengalis.

I analyzed the finger prints of 59 male and 48 female unrelated Bengalis in a rehabilitation camp of Dacca, Bangladesh. The most common pattern type in the Bengalis was the ulnar loop (53%), then whorls (40%); arches (5%) and radial loops (2%) were the least common. Radial loops occurred most frequently on the index fingers. I have shown the arch/whorl, whorl/loop, and pattern intensity indices, and I have presented ridge counts by individual digits and by total digital ridge count. Digital dermatoglyphics in the male Bangladeshis were similar to previous findings in male Brahmins of Bengal. However, there were more whorls and arches, fewer loops, and a higher mean total digital ridge count in the female Bangladeshis than in female Brahmins.     

Fixed and random effects in the variation of the finger ridge count: a study of fragile-X families.

A maximum-likelihood scoring technique for analysis of pedigree data allows for the concurrent estimation of random and of fixed effects in a quantitative trait. We included both types of effects in genetic models, to study the sources of variation in finger ridge count in 54 large families affected with the fragile-X disorder. The fixed effects were represented by fragile X and sex, and the random effects by environmental and genetic variance. We found a significant effect of fragile X in the mean of the finger ridge count on the thumb (finger 1) and index finger (finger 2), which had the lowest heritability and a negligible nonadditive component of genetic variance. This was in contrast with ridge counts on fingers 3 and 4, which showed little fragile-X effect, but high heritability and a significant nonadditive component. A contrast in genetic properties for ridge counts on fingers 1 and 2, compared with these counts on the remaining three fingers, may be relevant to increased selection pressures on functions of the thumb and of the index finger in evolution of modern man. We have also demonstrated an important effect of fragile X in increasing the additive variance in covariance, especially between male pairs. These findings suggest that the effect of the fragile-X genotype in finger ridge count is additive and superimposed on the normal hereditary variations in this trait.     

Quantitative finger dermatoglyphics in the Mediterranean region of Murcia,Spain

Quantitative finger dermatoglyphics have been analyzed in a Spanish population on the Mediterranean coast, from a sample of 347 individuals (163 males and 184 females) whose four grandparents were born in the studied region (Murcia). From the prints of the sampled individuals, radial, ulnar, and maximal ridge counts have been examined using classical methodology according to the pattern orientation. Kolmogorov test was used to evaluate the normality of the count values. Paired t-test, t-test for two samples, and Wilcoxon and Mann-Whitney non-parametric U test were used to explore bimanual and sexual differences. Maximal and radial ridge counts show similar distributions fitting into a normal distribution. Instead, ulnar values show a particular distribution clearly different from normality. The bilateral and sexual differentiation patterns reveal the divergence between the ulnar counts and the maximal and radial values. In comparison to other Iberian populations our results show a particular position of Murcia with the lowest TFRC values in the Spanish variation ranges.     

Quantitative digital dermatoglyphics in males and females of four Sardinian linguistic groups

Radial and ulnar ridge counts on each of the 10 fingers, total finger ridge count, bilateral summed radial and ulnar finger ridge counts, an index of asymmetry between homologous fingers and two indices of intraindividual diversity of finger ridge counts were used to identify biological relationships among Sardinian linguistic groups. Stepwise discriminant analysis of 26 digital traits of 1258 Sardinians, 647 females and 611 males, was carried out. The results indicate high intergroup heterogeneity; moreover, with p≤0.01 as F-to-enter and p≤0.05 as F-to-remove, only 5 of the 26 digital variables are in the model (URC R5, RRC L5, RRC R5, URC R4, URC L5). The pattern of interpopulation biological relationships shows a clearly distinct position of the Gallurian group (both males and females), which speaks an Italian dialect. It originated mainly from Corsican immigration to the Gallura region starting from the XVII century. While the properly Sardinian linguistic groups (Campidanian and Logudorian) and the Sassarian group, which speaks an Italian dialect that developed as a “lingua franca” during the Middle Ages (XII–XIV centuries) due to linguistic contact between Sardinians and Italians, are positioned close to one another. This pattern agrees more with the ethno-historical back-ground than with the linguistic one.     

赫哲族掌指纹特征研究

本文对166名健康赫哲族人的掌指纹进行了研究,其中男性86名,女性80名。本文列出了58个赫哲族掌指纹参数,将其中52个掌指纹特征输入电子计算机,进行了相关及主成份分析。并且,将赫哲族的掌指纹特征与汉族的掌指纹特征进行了比较。 结果表明:赫哲族的掌指纹特征是与汉族相似的,并且有自己的特征;双手同名指的相关系数大于非同名指,单手相邻指的相关系数大于相隔指;在有关掌指纹特征的研究中,指纹的重要性大于掌纹。     

Finger ridge-count variation in 45,X Turner's syndrome

Summary Finger ridge-counts of 109 45,X Turner's syndrome patients were compared to normal controls by means of discriminant functions. Each subject was represented by 20 variables, a radial and an ulnar count for each digit. Not only do Turner patients exhibit larger counts, but the distribution of counts over the digits is altered considerably. The Turnernormal differences appear to correspond to previously defined developmental fields.     

Variations on dermal ridges in nine population groups of maharashtra,india. III. Asymmetry and interdigital diversity

Variations in asymmetry and interdigital diversity for the three finger-dermatoglyphic traits, total finger ridge count (TRC), absolute total finger ridge count (ARC), and finger pattern intensity index (PII) have been studied here from a sample of 646 males belonging to nine population groups from Maharashtra, India. It is seen that at such local level of population differentiation the ridge count measures TRC and ARC discriminate the population better as compared to PII. A considerable amount of variations also exist in their asymmetries and interdigital diversities and these suggest the possibility of their genetic controls. Such genetic controls might mediate both asymmetry and interdigital diversity jointly, as there seems to be positive correlation between these measures with respect to all the three finger-dermatoglyphic traits.     

Relationships of epidermal ridge patterns with body measurements and their possible evolutionary significance

It is commonly believed that in humans epidermal ridge patterns are in regression relative to nonhuman primates, and they play no role in adaptive processes. In contrast with this we have found relationships between anthropometric and dermatoglyphic measurements in a sample of 61 normal males. Anthropometric variables included limb, trunk, head, and face measures. Dermatoglyphic variables included finger ridge counts and pattern intensities and ridge breadth in the palmar interdigital area II. The strongest relationship is between the type and size of pattern on the thumb and the breadth of ridges, and wrist width, which accounts for nearly 30% of the total variance in these traits. These findings identify previously unknown sources of variation in dermatoglyphic patterns and indicate that the dermatoglyphic-anthropometric relationships might have resulted from selection pressures in evolution of modern man.     

Fluctuation and directional asymmetry of the oppositely orientated finger ridge counts in Bulgarians

In a sample from Northeast Bulgaria (500 males, 500 females) fluctuating and directional asymmetries of the radial and ulnar finger ridge-counts were studied, each sex separately and finger-by-finger. Neither the ridge counts nor their fluctuating asymmetries show any considerable sex difference. In contrast, the curves of the ulnar and radial directional asymmetries, each of them being similarly distributed over the digits in both sexes, are contrasted in males and females. One interpretation is that the sex chromosomes exert a considerable effect upon the mediolateral developmental gradients and so cause a set of well expressed sex differences in the directional asymmetries of the ulnar and radial finger ridge-counts.     

Directional asymmetry of finger ridge counts in females of Sardinian linguistic groups

The data used in this study are the fingerprints of 744 females from 6 Sardinian linguistic groups. We analyzed 15 dermatoglyphic variables of directional asymmetry, namely the right vs left signed differences between i-th homologous fingers for larger ridge counts, radial counts and ulnar counts. Principal components analysis of the dermatoglyphic variables in the females of Sardinian linguistic groups revealed a pattern of biological relations among the groups which is consistent with their linguistic, but especially historical and demographic, backgrounds.     

Components of racial variation in finger ridge-counts

Principal components analysis was used to evaluate finger ridge–count variability as an indicator of genetic relationships between populations. The analysis was carried out on American White, American Black and African Black samples, each including both sexes. Each individual is represented as a vector of 20 counts, a radial and an ulnar count for each digit. No assumptions were made prior to analysis concerning the number of meaningful components, and all were examined sequentially. The first five eigenvectors extracted from the within-group correlation matrix have loadings very similar to those previously described by Roberts and Coope ('75). However, it is the component scores derived from the sixth eigenvector which show the most marked variation, accounting for 45% or more of the D²in all Black-White comparisons. A number of other components also show significant intergroup heterogeneity, but they often do not accord with what is known of the genetic relationships between the populations. Apparently a large amount of ridge-count variation is not genetically meaningful, at least as far as these populations are concerned.     

Genetic parameters of dermal patterns of ridge counts.

Dermatoglyphic traits including ridge counts and pattern type counts on fingers were studied in 711 families representing six racial groups in Hawaii. Heritability tesimates were derived from regressions of offspring on father, mother and mid-parent values as well as from full-sib correlations. These estimates varied from 0.23 for radial loops to 0.80 for total ridge count. The heritability estimates were lower for ridge counts of single hands or single digits.     

Finger patterns characteristics as determinants of total ridge count variability

The total ridge count (TRC) was viewed as a common composite trait with definite correlations between its components — the ridge counts (RC) of individual fingers. The TRC variability was accordingly examined as a function of the variability of these components. The distribution of pattern types on the fingers, the RC of patterns per total as well as per finger location, and the mean finger RC were all analyzed in relation to the RC variability and to a newly described phenomenon — the mutual influence on the RC variability of different patterns present concomitantly in an individual. It was concluded that the TRC variability is conditioned by the frequencies of the same genes which are responsible for the presence of the different finger pattern types. A high negative correlation coefficient, −0.901, was found between the pattern intensity index (PII) and the coefficient of variation of the TRC. The linear regression equation was: CV=90.75−4.20 PII. Biological isolation and the ensuing consanguinity may affect the TRC variability of a population by modifying the frequencies of these genes. This influence may be a decreasing as well as an increasing one. In contrast, when a common metric trait which is determined by additive genes without any dominance (as the TRC is frequently believed to be) is subjects to consanguinization effects, only a decrease in the variation is expected. The dermatoglyphics of 625 Jewish males were investigated and the general character of some dermatoglyphic regularities and trends was compared with and corroborated by data from the literature.     

Studies of X inactivation and isodisomy in twins provide further evidence that the X chromosome is not involved in Rett syndrome.

Rett syndrome (RS), a progressive encephalopathy with onset in infancy, has been attributed to an X-linked mutation, mainly on the basis of its occurrence almost exclusively in females and its concordance in female MZ twins. The underlying mechanisms proposed are an X-linked dominant mutation with male lethality, uniparental disomy of the X chromosome, and/or some disturbance in the process of X inactivation leading to unequal distributions of cells expressing maternal or paternal alleles (referred to as a "nonrandom" or "skewed" pattern of X inactivation). To determine if the X chromosome is in fact involved in RS, we studied a group of affected females including three pairs of MZ twins, two concordant for RS and one uniquely discordant for RS. Analysis of X-inactivation patterns confirms the frequent nonrandom X inactivation previously observed in MZ twins but indicates that this is independent of RS. Analysis of 29 RS females reveals not one instance of uniparental X disomy, extending the observations previously reported. Therefore, our findings contribute no support for the hypothesis that RS is an X-linked disorder. Furthermore, the concordant phenotype in most MZ female twins with RS, which has not been observed in female twins with known X-linked mutations, argues against an X mutation.     

Twinning and heteropaternity in chimpanzees (Pan troglodytes)

Unlike monozygotic (MZ) twins, dizygotic (DZ) twins develop from separate ova. The resulting twins can have different sires if the fertilizing sperm comes from different males. Routine paternity testing of a pair of same-sexed chimpanzee twins born to a female housed with two males indicated that the twins were sired by two different males. DNA typing of 22 short-tandem repeat (STR) loci demonstrated that these twins were not MZ twins but heteropaternal DZ twins. Reproductive data from 1926-2002 at five domestic chimpanzee colonies, including 52 twins and two triplets in 1,865 maternities, were used to estimate total twinning rates and the MZ and DZ components. The average chimpanzee MZ twinning rate (0.43%) equaled the average human MZ rate (0.48%). However, the chimpanzee DZ twinning rate (2.36%) was over twice the human average, and higher than all but the fertility-enhanced human populations of Nigeria. Similarly high twinning rates among African chimpanzees indicated that these estimates were not artifacts of captivity. Log-linear analyses of maternal and paternal effects on recurrent twinning indicated that females who twinned previously had recurrence risks five times greater than average, while evidence for a paternal twinning effect was weak. Chimpanzee twinning rates appear to be elevated relative to corresponding estimated human rates, making twinning and possibly heteropaternity more important features of chimpanzee reproductive biology than previously recognized.     

Digital dermal patterns in breast cancer

Fingerprints of 570 breast cancer cases and the same number of matched controls were obtained from the population-based finger print file in Hawaii for studying the association between breast cancer and digital dermal patterns and ridge counts. The results showed that breast cancer patients had a significant excess of radial loops on the left hand. It was also found that the frequency of ulnar loops on the left hand was significantly elevated for premenopausal women with breast cancer, whereas an excess of radial loops on the left hand was observed for the postmenopausal women with breast cancer. No significant difference for the total and absolute ridge counts was found between breast cancer patients and controls.     

Analysis of the Covariance Structure of Digital Ridge Counts in the Offspring of Monozygotic Twins

Improved methods for analysis of covariance structures now permit the rigorous testing of multivariate genetic hypotheses. Using J?reskog's Lisrel IV computer program we have conducted a confirmatory factor analysis of dermal ridge counts on the individual fingers of 509 offspring of 107 monozygotic twin pairs. Prior to the initiation of the model-fitting procedure, the sex-adjusted ridge counts for the offspring of male and female twins were partitioned by a multivariate nested analysis of variance yielding five 10 X 10 variance-covariance matrices containing a total of 275 distinctly observed parameters with which to estimate latent sources of genetic and environmental variation and test hypotheses about the factor structure of those latent causes. To provide an adequate explanation for the observed patterns of covariation, it was necessary to include additive genetic, random environmental, epistatic and maternal effects in the model and a structure for the additive genetic effects which included a general factor and allowed for hand asymmetry and finger symmetry. The results illustrate the value of these methods for the analysis of interrelated metric traits.     

Dermatoglyphics in juvenile hypertension.

Dermatoglyphics of 172 children and young adults (116 males, 56 females) with hypertension, 13-27 years old, were compared with those of 130 healthy male and 110 female controls. Several differences were observed between the two groups. Hypertensive patients had a somewhat lower frequency of fingertip ulnar loops, higher frequency whorls and a higher total finger ridge count. They also had a somewhat higher mean atd angle, significantly more frequent distal position of the axial triradius (mostly in t' position) and more missing axial triradii compared to controls. The differences between a-b ridge counts, the interdigital, thenar and hypothenar patterns were generally small and sometimes limited to one sex or one hand only. The observed differences seem to indicate a genetic influence in the etiology of essential hypertension.