| Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1995: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1994: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1993: ¥700,000 (Direct Cost: ¥700,000)
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| Research Abstract |
Variant patterns of dermatoglyphics on volar skin of man are useful in diagnosis of various congenital anomalies. The present study aimed at describing the normal pattern of dermatoglyphics on volar skin of mice and its embryological development for establishment of an animal model.
Mice have four kinds of pads on their volar skin : (1) digital pads, (2) interdigital and carpal (tarsal) pads, (3) caterpillar pads, and (4) cobblestone pads. The embryonic days on which these pads first appear are day 15 (vaginal plug=day 0) for interdigital pads, day 16 for digital pads, and days 17-18 for catepillar and cobblestone pads.
Dermatoglyphic examinations of mutant mice "meromelia" with various types limb malformations revealed that the palm skin of meromelia tended to be partially dorsalized. Expressions of Shh, Wnt-5a, and Wnt-7A were abnormal, and these findings suggest that these genes are related with dermatoglyphic patterning.
Transplacental exposure of various teratogens such as 5-fluorouracil, retinoic acid, acetazolamide, and methoxyacetic acid during limb organogenesis induced aberrant patterns of the pads in fetuses with agent and stage specificity. In cases of polydactyly or oligodactyly, the pad pattern changed according to the skeletal pattern. However, abnormal pad patterns were detected even in limbs without digital ray deficiencies. These results indicate that observation of dermatoglyphics is useful for detection of minor limb anomalies, and for detection of developmental toxicity of environmental chemicals.
Comparative observation of dermatoglyphics in mice, rats, moles, and rabbits suggested that pads have been evolved for adaptation to walking on the ground, grasping, and climbing.
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