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J M Opitz

Publications and source records attributed to J M Opitz.

At least 91 records · Page 5Linked to original sources
PubMed1992

[Developmental disorders of man. Part 2].

At the beginning of this century genetics arose out of developmental history (Entwicklungsgeschichte) as the science of the causal understanding of development. After Spemann's epochal discovery (justifiably rewarded with the Nobel Prize in 1935) of the organizer and the beginning of the experimental analysis of developmental fields, little or no progress was made until the last few years when a virtual revolution occurred in developmental biology. If nothing else, this revolution has re-inspired in medicine an enormous respect for developmental animal models which are homologous to the human condition in the strict sense of the term, both in formal (formalgenetischer) and causal (kausalgenetischer) respects. Thus, the earliest stages of development in the primary field (during gastrulation) and in the later mosaic of secondary, epimorphic fields, represents the harmonically coordinated and epigenetically regulated effects of many genes which (with of without imprinting) code for cellular adhesion molecules, the peptide regulatory factors, homeobox genes, retinoic acid receptors and many other genes. Some of these genes act as regulators of DNA transcription, and, until recently no clinically identifiable developmental attribute to their function was known in humans. However, just in the last few weeks we have witnessed the identification of a gene on 11p13 in humans which is a paired box- and homeobox-containing gene as the cause of human aniridia, with the identical (homologous) mutation in the mouse Pax-6 gene producing the Sey phenotype (small eye).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

A familial MCA/MR syndrome due to translocation t(10;16) (q26;p13.1): report of six cases.

A minute familial translocation t(10;16) (q26;p13.1) was detected in a family with 6 affected children in 2 generations and 9 carriers in 3 generations. This apparently unique translocation is associated with a deleterious syndrome which includes fetal hydrops, ascites, complex congenital heart defect, psychomotor retardation, failure to thrive, hypotonia, narrow palpebral fissures, abnormally modeled, apparently low-set ears, cleft palate, thumb abnormalities, hypogenitalism, inguinal hernia, and sparse hair. All children of known or presumed carriers have been either balanced or unbalanced carriers of this translocation.

Abnormalities, Multiple↗
PubMed1991

Clinical aspects of dermatoglyphics.

As demonstrated above, considerable progress has been made in the understanding of the associations between dermatoglyphics and various medical disorders, as a result of which dermatoglyphic analysis has been established as a useful diagnostic and research tool in medicine, providing important insights into the inheritance and embryologic development of many studied clinical disorders. Many unanswered questions and misconceptions still remain, though. Further well-designed investigations, avoiding the pitfalls of many earlier studies, will be needed to reevaluate some of the existing claims and to determine the real value of dermatoglyphics in medicine. The benefits of a dermatoglyphic examination in individual patients in clinical genetic practice are clear; a more widespread application of this tool by clinical geneticists and pediatricians should be encouraged. Embryologic and experimental dermatoglyphic studies clearly hold a considerable potential for a better understanding of the factors influencing the development of the epidermal ridge patterns. Utilized together with newly developed methods and insights gained in recent studies of other aspects of dermatoglyphics, they should significantly advance the studies of the relationship between dermatoglyphic variation and medical disorders.

Abnormalities, Multiple↗
PubMed1991

[Developmental abnormalities in humans].

Recently, tremendous advances have been made in our understanding of pre- and perinatal death and congenital anomaly, but many aspects of the field remain unknown and require the continued collaboration of workers in many clinical and basic science disciplines. Most of mankind dies before, not after birth, mostly due to chromosome abnormalities arising during pregenesis. A few trisomy 13 and 18 cases survive till birth by virtue of placental mosaicism; even trisomy 21 is an 80% prenatally lethal and a postnatally sublethal syndrome. Most aneuploid individuals surviving postnatally have sex chromosomes abnormalities (47,XXY, 47,XYY, 47,XXX). Until recently the term "monsters" was applied to many abnormalities of blastogenesis--i.e. the disruptions and malformations arising during the first 4 weeks of embyronic development (till the end of mesoderm formation). This includes not only acardia/acephaly, but also holoprosencephaly, sirenomelia, gross defects of cord, body wall and -stalk formation and conjoined twins, but also non-conjoined monozygotic twins with apparent high prenatal mortality and a high incidence of midline anomalies. One of the most important recent insights has been that associations, e.g. the VACTERAL association, and the relatively characteristic combination of anomalies seen in infants of diabetic mothers, represent disruptions of blastogenesis. The latter represent a particularly satisfying development in the field since it has been shown that control of the woman's blood sugar levels before, during and after conception helps to reduce the high incidence of defects of blastogenesis in infants of diabetic mothers. Most malformations arise during organogenesis in secondary or epimorphic fields and mostly represent anomalies of incomplete, less commonly of abnormal differentiation. An important distinction must be made between mild malformations (all-or-none defects of organogenesis) which are relatively innocuous and common in the population but never normal, and minor anomalies which are graded defects of phenogenogenesis (i.e. of the developmental processes during the fetal period (weeks 8-10 p.c.), and the most frequent anomalies in aneuploidy syndromes with resulting loss of family resemblance.(ABSTRACT TRUNCATED AT 400 WORDS)

Chromosome Aberrations↗
PubMed1990

GAPO syndrome (McKusick 23074)--a connective tissue disorder: report on two affected sibs and on the pathologic findings in the older.

GAPO syndrome was described in 12 patients from 7 families. Constant manifestations include dwarfism, alopecia, pseudoanodontia, and a peculiar, "geriatric" facial appearance. We describe the autopsy findings and all available clinical data on one deceased patient and his living affected sister, previously reported as short abstracts (Epps et al.: Cienc Cult 29(Suppl):740, 1977; Wajntal et al.: Cienc Cult 34(Suppl):705, 1982). Both had the characteristic anomalies of this syndrome but optic atrophy was absent; instead, they had glaucoma and keratoconus; hypogonadism was present in both patients. Biopsy and autopsy findings show that the GAPO syndrome is a dyshistogenetic sequence due to accumulation of extracellular material and thus should be called GAPO dysplasia. We suggest that the basic defect in this autosomal recessive disorder is possibly related to a lack of breakdown of the extracellular components, perhaps due to an enzyme deficiency involved in the metabolism of extracellular matrix.

Abnormalities, Multiple↗
PubMed1990

"C" trigonocephaly syndrome: clinical variability and possibility of surgical treatment.

We report on 3 new cases of C trigonocephaly syndrome. In addition to the findings characteristic of this condition, one of the patients also had a large omphalocele. This patient was referred from a suburban hospital with a diagnosis of Down syndrome, stressing the fact that C syndrome is still under-recognized and underdiagnosed. Another patient was diagnosed at birth and immediately submitted to craniosynostectomy. A second operation was performed 7 months later resulting in normal brain growth and close to normal psychomotor development at 3 years, in contrast to the third patient, who was not treated surgically and was severely retarded at 4 years.

Abnormalities, Multiple↗
PubMed1990

Reflections on the pathogenesis of Down syndrome.

Present efforts to identify, isolate, and characterize in molecular terms the "consensus" segment of 21q sufficient to cause most of the major and some of the most characteristic minor manifestations of Down syndrome will soon provide answers to many questions. However, we think that a reductionist approach to explain the Down syndrome phenotype in a "linear" manner from the DNA sequence of the segment will be doomed to failure from the outset because of the open, complex, nonlinear, hierarchical nature of morphogenetic systems. Neo-Darwinism is under strong attack; most genetic changes accumulated over time may very well be of neutral effect, and detailed studies in several related groups of vertebrate species has shown that molecular and organismal evolution are largely independent of one another. It has been pointed out recently that biology lacks a theory of ontogenetic and phylogenetic development, and that a purely "genocentric" view of biology at the expense of the complexly hierarchical intrinsic epigenetic attributes of developmental systems is "out of focus with respect to ... biological organization and morphogenesis," and may be "a residue of nineteenth century romantic idealism." Down syndrome impresses us as a paradigm of increased developmental variability due to a deceleration of the rate of development (neoteny) with many anomalies of incomplete morphogenesis (vestigia), atavisms, increased morphometric variability with many decreased means, increased variances, and increased fluctuating asymmetry. These abnormalities, together with highly increased risk of prenatal death and postnatal morbidity, impaired growth, and abnormal CNS and gonadal structure and function characteristic of most aneuploidy syndromes, suggest to us that the pathogenesis of Down syndrome is best viewed in terms of the mechanisms of speciation. Transgenic experiment involving sequential or overlapping pieces of "the consensus segment" on distal 21q22.1-22.3 may help decide to what extent the Down syndrome phenotype can be resolved into the additive effect of several pleiotropic oligogenes with epistatic interaction or the indirect secondary "mass" effect of a specific segment of 21q with epistatic interaction involving multiple loci on 21q and other chromosomes.

Chromosomes, Human, Pair 21↗
PubMed1990

Microcephaly: general considerations and aids to nosology.

Microcephaly is defined as an occipito-frontal head circumference (OFC) 2 or more standard deviations below the mean for age and sex using the new Roche et al. [Pediatrics 1987;79:706-712] charts, and corrected for parental OFC by the method of Weaver and Christian [J Pediatr 1980;96:990-994]. "Relative" microcephaly, i.e., a small head on a small child, may be associated with a much better intellectual prognosis than absolute microcephaly, although the average IQ of children with absolute microcephaly ascertained in a normal school system is normal when compared with that of appropriate control children. "Primary" microcephaly means an abnormal OFC at birth (corrected for gestational age and length), and "secondary" microcephaly a normal birth OFC with later, acquired microcephaly due to deceleration of brain growth reflecting infection, trauma, intoxication, metabolic disease, the Rett syndrome, or a true CNS degenerative disease. Some cases of syndromal microcephaly may be associated with normal intelligence including some "primordial dwarfs," children with Dubowitz syndrome, FAS, mild SC-Roberts syndrome, and an occasional Brachmann-de Lange individual. The nosology of (syndromal) microcephaly is extraordinarily complex and requires the assistance of special library resources and information retrieval expertise. At a minimum, it requires McKusick's Catalog of Mendelian Inheritance in Man (MIM); however, we find that our work is greatly enhanced by recently developed electronic databases such as MIM-online (OMIM), POSSUM, SYNDROME, and MEDLINE, as well. Three groups of syndromal and non-syndromal microcephaly are discussed selectively in order to illustrate the marvels of pleiotropy in human development and its abnormalities and the difficulties encountered in splitting and lumping entities with overlapping manifestations.

Abnormalities, Multiple↗