title: Ridge course of the whorls: classification and methods.
abstract: In dermatoglyphic methodology the system of gross classification of digital pattern types needs modifications.  More attention should be focussed on the study of minute morphological variations among pattern types in order to understand fully the genetic mechanisms involved in pattern variations.  A systematic classification to record many of the morphological peculiarities is lacking.  The paper proposes a classification and methods of identification of the direction of the course of the ridges inside the pattern area of true whorls.  In all, nine ridge course types are identified, named and described.  Data analysed on the basis of the above methods and classification reveal significant bilateral differences for clockwise and counter-clockwise types of ridge directions.  Mode of inheritance, bisexual differences, etc., of the polymorphic course of these ridges should be studied.  Its usefulness in the field of personal identification, population genetics and medicine should also be evaluated.
mesh_terms: D003878:Dermatoglyphics / Q000145:classification*; D005260:Female; D005385:Fingers; D007839:Functional Laterality; D005828:Genetics, Population; D006801:Humans; D008297:Male; D012737:Sex Factors