Ridge Dissociation Research Articles

Further evidence that congenital dermatoglyphic abnormalities are associated with psychosis: a twin study.

The presence of abnormal palmar flexion creases (APFC) and dermatoglyphic ridge dissociation (RD) may constitute enduring evidence of a prenatal insult that occurred before the third trimester of intrauterine life. We examined these dermatoglyphic abnormalities in a twin study of psychotic disorders. RD and APFC were analyzed in a monozygotic (MZ) twin sample from the Maudsley Hospital in London (11 normal control pairs, 16 pairs concordant for psychosis, 9 pairs discordant for psychosis, 1 concordant triplet, and 1 triplet with one affected member). The risk of either RD or APFC was 44 percent in affected twins and 20 percent in nonaffected twins (odds ratio = 3.25, 95% confidence interval: 1.03-10.31; one-sided p = 0.023). In the group of MZ twins discordant for psychosis, discordance for RD or APFC always paralleled discordance for psychosis (one-sided p = 0.078), suggesting the operation of nongenetic factors. The results confirm previous work suggesting the possibility that nongenetic factors early in pregnancy contribute to the liability to develop psychosis in later life.

Congenital dermatoglyphic malformations in severe bipolar disorder

Dermatoglyphic alterations may be the result of early prenatal disturbances thought to be implicated in the aetiology of psychiatric illness. In order to test this hypothesis in the particular case of bipolar disorder, we assessed two congenital dermatoglyphic malformations (ridge dissociation (RD) and abnormal features (AF)) and two metric dermatoglyphic traits (total finger ridge count (TFRC) and total a-b ridge count (TABRC)) in a sample of 118 patients with chronic DSM-III-R bipolar illness, and 216 healthy controls. Bipolar cases showed a significant excess of RD and AF (OR=2.80; 95% CI: 2.31–3.38) when compared with controls. In the cases, the presence of anomalies was associated with earlier age of onset. No differences were found for TFRC and TABRC. No associations were found with sex or familial morbid risk of psychiatric disorders. Our findings add further weight to the suggestion that early developmental disruption is a risk factor for later bipolar disorder.

Fluctuating asymmetry and vertebral malformation. A study of palmar dermatoglyphics in congenital spinal deformities.

Prints of palmar dermatoglyphics (epidermal ridges) of individuals with congenital vertebral anomaly were compared, using symmetry criteria, with those of healthy control individuals. Asymmetries have been reported in adolescent idiopathic scoliosis and, from other centers, in other congenital anomalies, such as cleft lip and palate. Application of these methods to congenital vertebral anomaly seemed promising. To challenge the hypothesis that, in congenital vertebral anomaly, epigenesis was disrupted by nonspecific physiologic stress during the embryonic period, resulting in anatomic malformations. Dermatoglyphics (palmar epidermal ridges) are formed at the end of the embryonic period under genetic control and do not change thereafter. They thus give an indication of the stability or otherwise of development at that early stage. This led to the hypothesis that congenital vertebral anomaly results from destabilization of genetic developmental control in the embryonic period. The dermatoglyphics of 126 healthy control individuals and 99 people with congenital vertebral anomaly were compared quantitatively, using right-left differences of atd angles and ab, bc, and cd ridge counts. Fluctuating asymmetry (a significantly increased variance about the mean) was observed in individuals with congenital vertebral anomaly. This is a measure of instability of genetic development processes and the increased probability that these processes will be destabilized by environmental stress during ontogeny. They also showed an increased incidence of ridge dissociation, suggestive of a generalized insult during the embryonic period. These findings suggest that congenital vertebral anomalies arise from a nonspecific insult during the embryonic period that destabilizes the developmental control systems and may result in congenital malformations of any organ undergoing concurrent epigenesis.

Congenital absence of dermatoglyphs

Congenital absence or unusual patterns of human dermatoglyphs (fingerprints) occur in several syndromes that are rare and poorly understood. The abnormalities of dermatoglyphs fall into four categories: complete absence, ridge hypoplasia, ridge dissociation, and ridges-off-the-end. Complete congenital absence of ridges is an exceedingly rare syndrome that consists of neonatal blisters and milia, adult traumatic blistering and fissuring, absence of sweating, contracture of digits, and absence of dermatoglyphs on the hands and feet. The syndrome is inherited in an autosomal dominant pattern, and only two kindreds have been described in the literature. We describe a newly identified patient and kindred with findings similar to the previously reported cases and review the clinical and histopathologic findings of this syndrome.

Partial sweat gland aplasia in incontinentia pigmenti Bloch-Sulzberger. Implications for nosologic classification.

Dermatoglyphic investigation of palm prints in patients with Incontinentia pigmenti revealed in five of eight cases a partial ridge dissociation with lack of sweat gland pores. This disease can, therefore, be accepted as a second X-linked anhidrotic ectodermal dysplasia, which, however, is only segregated in the female.

Some dermatoglyphic features of Australian aboriginals from Mornington Island

AbstractTopologically significant dermatoglyphic patterns on palms and fingers have been analyzed in a sample of 118 Lardiil and 37 Kaiadilt males and females living on Mornington Island. The purpose of this analysis has been to demonstrate the applications of the topological classification in comparative studies and to point out some general developmental problems which have emerged from dermatoglyphic study of distant populations. The results are presented in the form of distributions of total pattern types on palms and on a set of five or 10 fingers, frequencies of pattern elements, and mean pattern intensities on different palmar areas and on individual fingers, and of intercorrelations between different patterns and different fingers. Moreover, finger ridge counts have been analyzed with respect to bilateral asymmetry. A sample of Australian aboriginals is compared with 300 individuals of British origin of corresponding sex and with some data on Polish family and twin samples.The results indicate that pattern intensity is considerably increased on fingers II, III, and IV and somewhat decreased on palms, mainly on account of much lowered frequency of some hypothenar patterns, while the patterns on the radial border of the palm are increased, a deviation being more pronounced in the females. The intercorrelations between fingers for pattern intensity and ridge counts are lowered. A possible relationship of these findings to peculiarities in the morphological structure of the hand in the aboriginals, as distinguished from that of the white Europeans, is discussed. Moreover, a lack of sexual dimorphism in finger ridge count and a high proportion of ridge dissociation in this sample indicates the need for cytogenetical investigation, especially towards peculiarities of the X chromosome, but other possible causes for these deviations should also be considered.

The dermatoglyphic and clinical features of the 9p trisomy and partial 9p monosomy syndromes.

The physical and dermatoglyphic features obtained from published reports of 128 patients with the trisomy 9p syndrome and 27 patients with the partial 9p monosomy syndrome are tabulated. This information is also provided on two new individuals with each of these chromosomal disorders. The dermal ridge patterns and palmar creases of trisomy 9p which are most helpful from a diagnostic standpoint are zygodactylous or absent palmar digital triradii, brachymesophalangy, reduced total finger ridge count, complex thenar/ID I patterns, transverse palmar ridge alignment, simian creases, distal axial triradii, and great toe and hallucal arch patterns. The characteristic features in partial 9p monosomy include dolichomesophalangy with accessory finger flexion creases, digital whorl patterns and elevated total finger ridge count, distal axial triradii, simian creases, and palmar dermal ridge dissociation.

Dermatoglyphs in congenital heart disease.

The palmar dermatoglyphs of 800 patients with anatomically proven congenital heart disease were compared with prints from 1000 controls. A review of the previous studies revealed major technical deficiencies, and the present study failed to confirm most of the previously reported positive findings. An overall increase in the incidence of hypothenar patterns was found, probably explaining the previous suggestion of increased atd angle in congenital heart disease. A large number of statistical comparisons inevitably produced a few 'significant' results, most of which were inconsistent in various ways. Two percent of cases were found to have rare epidermal ridge malformation, ridge dissociation. The nature of the relationship between this and congenital heart disease is obscure. Claims that there are diagnostically useful dermatoglyphic changes in congenital heart disease can be disregarded.

Congenital malformations of human dermatoglyphs.

A classification for congenital malformations of dermatoglyphs is presented, dividing them into ridge aplasia, ridge hypoplasia, ridge dissociation, ridges-off-the-end, and a combination of the last two. The medical and genetic significance of these are considered in the light both of previous published cases and of new material. Malformations of dermatoglyphs are important as physical signs in paediatric diagnosis.

Severe ridge dissociation and "ridges-off-the-end" in the same person.

A man is reported with the almost unique combination of severe ridge dissociation and ridges running vertically off the end of his fingertips. Two of his children have mild ridge dissociation, and his parents were first cousins.

Fingerprints in Schizophrenia

Report is made of a study of fingerprints on a series of schizophrenics. This series was comprised of 100 males, rigidly screened as to diagnosis and possible complicating conditions and factors. Certain special trends in fingerprint patterns were noted. In addition, there was found a tendency to ridge dissociation attributed to disturbance during the period of ridge differentiation in fetal life, and observed in a variety of other conditions and states. These findings bear on the matter of constitution in schizophrenia; i.e., the nature and significance of the host in this disorder. Noteworthy is the suggestion of basic genotypic insufficiency or deficit reflected in the development of various disorders and abnormalities. The emerging significance of dermatoglyphics as a clinical instrument and genetic lead is emphasized.