A Computerized data base resource for dermatoglyphics research.

The study of the ridged skin on the plantar and palmar surfaces of man is termed "dermatoglyphics" and has been the subject of various scientific investigations particularly in medicine and human genetics. Since the dermal configurations are completely determined by the fourth moth of gestation and are unaffected by environment thereafter, dermatoglyphics features remain intact as markers reflecting the genetic constitution and forces that bear on development in the intrauterine environment prior to this time. Associations between dermatoglyphic features and disease, then, suggest a common antenatal phenomenon. Whether this effect is genetic, developmental, or environmental in origin, such findings can further the understanding of the etiology of disease. Due to the ability to inexpensively and noninvasively examine the ridged skin, confirmed associations may allow dermatoglyphic features to be used in a screening situation to aid in the assessment of disease risk. Similarly, the strong heritability demonstrated by dermatoglyphic traits has resulted in considerable genetic research in view of the prospect of using such features as genetic markers. Although many associations with disease have been reported, few have been confirmed. Genetic marker studies require traits of major gene inheritance, but dermatoglyphic features have been repeatedly shown to result from the additive effects of several loci. A review of the literature suggests that a successful search for disease associations and major gene influences in dermatoglyphics requires that new features be defined and examined on a pattern-area-specific basis. An exploratory approach to dermatoglyphics research would identify variables and pattern areas of particular interest in these endeavors. Such an approach requires a computerized resource that can be used to: (1) rapidly extract features from dermal ridge patterns, (2) preserve the contextual meaning of the data in storage and allow for ready access to raw and synthetic variables, and (3) control and use dependent attributes such as genetic relationships and sex. In this dissertation, a computerized data base resource for dermatoglyphics research is described. An algorithm to determine the ridge count of a fingerprint based on the spatial periodicity of a ridged field is developed and tested on approximately 1500 digits. Family relationships within the data base are controlled using a set of identification pointers that link family members together according to their genetic associations. The structure employed to store both these pointers and the fingerprint data reflect the contextual meaning inherent in the information. As an example of the utility of the resource, an association between certain fingerprint features and myocardial infarction (MI) reported in Japanese males was investigated on a Caucasian sample. In addition, an exploratory search for major gene components in dermatoglyphic variables and pattern areas was undertaken using a battery of genetic measures evaluated on a set of nuclear families. A sample of 100 Japanese MI victims were found to have a significantly higher frequency of whorls and double loops as well as elevated mean finger-specific and summed ridge count values over a similar group of 666 subjects showing no evidence of MI. Although these results could not be statistically reproduced in a comparison of 62 male MI victims and 69 controls from Utah, consistent differences in the pattern type frequencies and mean ridge counts in the two studies suggest common antenatal forces in fingerprints and certain types of heart diseases in the two populations. A search for departures from the expected behavior of a polygenic multifactorial scheme of inheritance, consistent across all the genetic measures evaluated, suggests possible major gene influences on dermatoglyphic traits expressed on the ulnar and radial digits.