Path analysis of palmar ridge counts.

The methods for path analysis of family resemblance (Rao et al., '74) are employed to test hypotheses concerning the inheritance of a-b, b-c and c-d palmar ridge counts using the correlation data of Pateria ('74). Homogeneity chi-square tests of the various familial correlations provide no evidence for sex-linkage of either kind, and also suggest that maternal effects are absent. The path coefficient model employed here involves heritability (additive) and common sibling environment. Variance components show that both heritability and common environment are significant, and account for most of the variation at each of the three ridge count area; b-c has the highest heritability, significantly higher than that for a-b or c-d.     

Effect of prenatal exposure to anticonvulsant drugs on dermal ridge patterns of fingers

BACKGROUND: An altered frequency of specific dermal ridge patterns on fingertips, such as an increased number of arches, has been observed in children exposed in utero to anticonvulsants and other teratogens. Asymmetry of the distribution of dermal ridge patterns has been attributed to environmental exposures and genetic factors. METHODS: We evaluated all of the dermal ridge patterns of 66 children who had been exposed to either the anticonvulsant phenytoin alone or phenytoin and phenobarbital. We determined the frequency of each pattern, concordance between the fingers on the left and right hands, sex differences and total ridge counts in the drug-exposed children and compared them to the findings in 716 unexposed comparison children. The frequency of each pattern was established in comparison to the most common type of pattern (ulnar loop), which showed that there were alterations in the frequency of arches, radial loops and whorls on specific fingers. RESULTS: Eight (12.1%) of 66 children had three or more arch patterns, with all but one having been exposed to phenytoin and phenobarbital. Only one of these eight children was considered by the masked examiner to have fingernail hypoplasia. There was no evidence of asymmetry in the anticonvulsant-exposed children. There were minor differences in the distribution of total ridge count. CONCLUSIONS: Subtle differences in several dermal ridge patterns, not just arch patterns, were present in anticonvulsant-exposed children, primarily in those exposed to polytherapy: phenytoin and phenobarbital.     

Genetic basis of a-b, b-c and c-d ridge counts on human palms

The mechanism of inheritance of ridge count of palmar interdigital areas has been studied among Brahmans of Sagar town of Central India. The correlation coefficients between ridge counts in various family relationships lend support to the concept of an additive genetic model, especially for the b-c or second interdigital area.     

Genetic basis of a-b,b-c and c-d ridge counts on human soles

The mechanism of inheritance of ridge count of plantar inter-digital areas has been studied among Brahmans of Sagar town of Central India. The correlation coefficient between ridge counts in various family relationships lend support to the concept of an additive genetic model.     

Genetics of plantar interdigital ridge counts

The genetics of interdigital ridge counts of soles has been studied in a homogeneous Brahmin population of Andhra pradesh, India. The parameters considered are a-b, b-c and c-d ridge counts. A new measure - total plantar interdigital ridge counts (TPtIRC) - has been defined and an attempt has been made to evaluate the mode of inheritance of this trait. The results of the present study do not fully support the earlier conclusions regarding the genetics of a-b, b-c and c-d ridge counts.     

Digital ridge counts and genetic fields

Summary Principal components analysis of quantitative digital dermatoglyphics in a large Oxfordshire sample, subdivided into male, female, urban, and rural subsamples, suggests several distinguishable components. These appear meaningful biologically in that they resemble factors of limb growth, as suggested by evidence from disturbances in limb extremity development. The components are consistent in all four subsamples and are very similar to those identified in a large sample of Berkshire data. It is suggested that digital quantitative dermatoglyphic variation may provide an example of genetic field theory.     

家族性耳聋者的掌纹嵴数

本文测量了耳聋患者的a-b,a-d和td纹嵴数,并比较了各个患者的皮纹学差异。资料收集自印度Punjabi Khatri和Arora地区的208名家族性遗传性耳聋者,其中男性118名;女性90名,对照组228名Punjabi地区正常人,其中男性128名,女性100名,本研究表明,与对照组相比,耳聋组的‘a-b’,‘a-b’和‘td’纹嵴数偏低。     

Diversity of palmar pattern ridge counts in Iranian populations

We analyzed bilateral palmar prints of 3,158 individuals from 13 Iranian populations of diverse origins for palmar pattern ridge counts. Right palms did not show greater counts than the left in the majority of the populations studied. Highly significant interpopulational variation was observed for most palmar areas of both males and females. Dendrograms of males and combined sexes showed a good fit with the ethnohistoric background of the populations studied. The results thus demonstrate variation in the palmar pattern ridge counts of populations of diverse origins and may be used as a good measure of population distance.     

Diversity in palmar pattern ridge counts among 12 Iranian populations

Bilateral palmar prints of 604 male individuals from 12 Iranian groups, six Mongoloid and six Caucasoid, have been analyzed for palmar pattern ridge counts (PPRC). Highly significant variation has been observed in the size of the palmar patterns in all the configurational areas among the Iranian groups. The distance analysis based on PPRCs differentiated the Iranian Mongoloid from the Iranian Caucasoid groups into distinct clusters. The pattern of differentiation based on PPRCs explained the ethnohistoric relationships between the Iranian groups as well as between the Iranian and the 20 Caucasoid groups from India much better than the palmar pattern frequencies. The results of this study demonstrate the existence of variation in the size of the palmar patterns across different populations within an ethnic group, as well as that among different ethnic groups, and seems to be a better indicator of interpopulational diversity than the palmar pattern frequencies.     

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.     

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.     

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.     

Genetic studies of the Syrian hamster III. Variation of dermal pigmentation

Summary An inherited modification of the dermal pigmentation of the Syrian hamster is described. The distribution of this pigmentation is variable in the normal hamster, especially that in the region of the genitalia of the male. However, the variation described here surpasses in extent this usual variability and, in particular, either partially or completely removes pigment from the ear pinna. This part was chosen as representative of the modification in general. The inheritance may be monogenic, with considerable impenetrance or, as may be more probable, may be polygenic. The complete suppression of pigment may be the consequence of the time of onset of the modification.     

Genetic analysis of dermatoglyphic patterns in twins.

Analysis of variance was performed on 71 dermatoglyphic variables in 424 twin sets. Using a method of twin analysis estimates of genetic variance were obtained. 54 of the variables were quantitated using a scoring system with modifications of arch or no pattern = 0, loops = 1, whorl = 2. The results indicated a significant genetic influence in most pattern areas. Patterning was more genetically controlled in the hand than in the foot. The hallucal area had the most significant genetic component of the foot while the patterns in the thumb had nonsignificant components of genetic variance. The thumb deviated from patterning in the rest of the fingers and may be more closely related to big-toe patterning.