Genetic service delivery: infrastructure, assessment and information.

Identification of genomic determinants of complex disorders such as cancer, diabetes and cardiovascular disease has prompted public health systems to focus on genetic service delivery for prevention of these disorders, adding to their previous efforts in birth defects prevention and newborn screening. This focus is consistent with previously identified obligations of the public health system as well as the core functions of public health identified by the Institute of Medicine. Models of service delivery include provision of services by the primary care provider in conjunction with subspecialists, provision of services through the medical home with co-management by genetics providers, provision of services in conjunction with disorder-specific treatment centers, and provision of services through a network of genetics clinics linked to medical homes. Whatever the model for provision of genetic services, tools to assist providers include facilities for outreach and telemedicine, information technology, just-in-time management plans, and emergency management tools. Assessment tools to determine which care is best are critical for quality improvement and development of best practices. Because the workforce of genetics providers is not keeping pace with the need for services, an understanding of the factors contributing to this lag is important, as is the development of an improved knowledge base in genomics for primary care providers.

Measuring contributions to the research mission of medical schools.

The authors of this article, who were the members and staff of a research panel formed by the AAMC as part of its mission-based management initiative, reflect on the growing interest in quantitative information in the management of the research mission of medical schools. They note the serious limitations of any such system of measures for research, particularly its inability to represent directly the quality of the research effort. Despite these concerns, the authors acknowledge that leaders in academic medicine have always used quantitative measures in one form or another to compare performance or assess progress. Two factors appear to be driving increases in this practice: (1) the need to demonstrate to institutional stakeholders that resources are being used wisely and that the school's performance justifies continued investment in the research mission; and (2) the need to fashion an economic strategy to manage precious institutional resources, particularly research space. Given these realities, the authors offer guidelines for the proper development and use of measures to assess contributions by faculty, departments, and institutions to the research mission. They also comment on the measures most commonly used in four areas: grants and other revenue-generating activities; publications; faculty members' research reputation and contributions to the national research enterprise; and support to the general research mission of the school. The authors conclude that quantitative information can help institutional leaders in important management decisions. However, the potential for misuse is great. The key is always to regard this information as an aid to judgment, not a substitute for it.

Congenital anomalies and anthropometry of 42 individuals with deletions of chromosome 18q.

Deletions of chromosome 18q are among the most common segmental aneusomies compatible with life. The estimated frequency is approximately 1/40,000 live births [Cody JD, Pierce JF, Brkanac Z, Plaetke R, Ghidoni PD, Kaye CI, Leach RJ. 1997. Am. J. Med. Genet. 69:280-286]. Most deletions are terminal encompassing as much as 36 Mb, but interstitial deletions have also been reported. We have evaluated 42 subjects with deletions of 18q at our institution. This is the largest number of individuals with this chromosome abnormality studied by one group of investigators. Here we report the physical findings in these individuals. We have compared our findings with those of previously reported cases and have found a significantly different incidence of several minor anomalies in our subjects. We also describe here several anomalies not previously reported in individuals with deletions of 18q, including short frenulum, short palpebral fissures, disproportionate short stature, overlap of second and third toes, and a prominent abdominal venous pattern. Characteristics found in subjects were analyzed for correlation with cytogenetic breakpoints. Several traits were found to correlate with the extent of the deletion. Large deletions were associated with significantly decreased head circumference and ear length as well as the presence of proximally placed and/or anomalous thumbs. Individuals with the smallest deletions were more likely to have metatarsus adductus. Although relatively few genotype/phenotype correlations were apparent, these data demonstrate that correlations with breakpoint are possible. This implies that more correlations will become evident when the more precise molecularly based genotyping is completed. These correlations will identify critical regions on the chromosome in which genes responsible for specific abnormal phenotypes are located.

Genetics education for primary care providers in community health settings.

Patients who are in need of genetic services are often inappropriately managed, in part due to inadequate knowledge of genetic issues among primary health care providers. The purpose of this study was to determine the effect of a genetics education program on the knowledge and attitudes of primary care providers in community health settings. A total of one hundred twenty-one primary care providers who work in Texas Public Health Region VIII participated in an educational program designed to provide basic genetics information. A one-group pretest-posttest design was used to assess knowledge and attitudes of subjects, and comparisons were made pre and post intervention. Pretest assessment revealed less than adequate knowledge about basic genetic principles and relatively positive attitudes among the subjects. Following the program, there were statistically significant increases in both knowledge about genetic conditions (P = .001) and attitudes toward provision of genetic services (P = .001). These results indicate that primary health care providers, motivated to learn complex materials and new skills in order to assist their patients, can do so in a relatively short time period.

Growth hormone insufficiency associated with haploinsufficiency at 18q23.

Growth hormone insufficiency is a common cause of growth failure in children with the 18q- syndrome. Individuals with this syndrome have a deletion as large as 36 Mb from the long arm of chromosome 18. We have evaluated 33 children with this syndrome for growth hormone production and have identified a region of approximately 2 Mb, which is deleted in every growth hormone insufficient patient. Two genes contained in this region, myelin basic protein, and the galanin receptor, are candidate genes for the growth hormone insufficiency phenotype.

Magnetic resonance imaging demonstrates incomplete myelination in 18q- syndrome: evidence for myelin basic protein haploinsufficiency.

Magnetic resonance imaging (MRI) and MRI relaxometry were used to investigate disturbed brain myelination in 18q- syndrome, a disorder characterized by mental retardation, dysmorphic features, and growth failure. T1-weighted and dual spin-echo T2-weighted MR images were obtained, and T1 and T2 parametric image maps were created for 20 patients and 12 controls. MRI demonstrated abnormal brain white matter in all patients. White matter T1 and T2 relaxation times were significantly prolonged in patients compared to controls at all ages studied, suggesting incomplete myelination. Chromosome analysis using fluorescence in situ hybridization techniques showed that all patients with abnormal MRI scans and prolonged white matter T1 and T2 relaxation times were missing one copy of the myelin basic protein (MBP) gene. The one patient with normal-appearing white matter and normal white matter T1 and T2 relaxation times possessed two copies of the MBP gene. MRI and molecular genetic data suggest that incomplete cerebral myelination in 18q- is associated with haploinsufficiency of the gene for MBP.

Preferential loss of the paternal alleles in the 18q- syndrome.

Individuals with the 18q- syndrome have variable deletions from the long arm of chromosome 18. They also exhibit a highly variable phenotype. To correlate genotype with phenotype accurately, extensive molecular and phenotypic analyses are needed on each affected individual. As a part of this analysis, we have determined the parental origin of the deleted chromosome in 34 individuals with the 18q- syndrome. We have found that 85% of the de novo deletions are paternal in origin. The percentage of fathers of individuals with paternally derived deletions who were > 30 years old was (not significantly) greater than that of the general population. The mothers of individuals with maternally derived deletions were near an average age for childbearing compared to the general population. Individuals with maternally derived terminal deletions had breakpoints as varied as those with paternally derived deletions. These results are consistent with the hypothesis that the reduced incidence of maternally derived deletions is not due to reduced viability, since individuals with large maternally derived deletions of chromosome 18q were found. We hypothesize that the prevalence of paternally derived deletions is due to an increased frequency of chromosome breakage in male germ cells. These results are consistent with results observed in other segmental aneusomies in which there is a high incidence of paternally derived deletions.

Growth hormone deficiency associated in the 18q deletion syndrome.

The 18q- syndrome is one of the commonest deletion syndromes. Clinical characteristics are variable but may include: hypotonia, tapered digits, "carp-like" mouth, mental retardation, and hearing impairment. Growth failure (GF; both weight and height < 3%) was reported in 80% of affected individuals. We evaluated growth hormone (GH) sufficiency in 5 18q- syndrome patients, 3 of whom had growth failure (< 3% weight and height); the remaining 2 had normal growth parameters. Laboratory evaluation of growth included measurement of IGF-1, IGFBP-3, bone ages and GH response to pituitary provocative agents. Three patients failed to produced adequate GH following stimulation testing. Of 3 patients with inadequate GH production, 1 had normal growth (above 3%). Only 1 of 5 patients had normal GH production and normal growth parameters. Our findings to date suggest that GH deficiency is common in individuals with the 18q- syndrome. The pathogenesis of this finding is unknown. We postulate that a gene(s) on 18q is involved in GH production.

Short-limb dwarfism and hypertrophic cardiomyopathy in a patient with paternal isodisomy 14: 45,XY,idic(14)(p11).

Uniparental disomy (UPD) has been shown to result in specific disorders either due to imprinting and/or homozygosity of mutant alleles. Here we present the findings in a child with paternal UPD14. Ultrasound evaluation was performed at 30 weeks of gestation because of abnormally large uterine size. Pertinent ultrasound findings included polyhydramnios, short limbs, abnormal position of hands, small thorax, and nonvisualization of the fetal stomach. Post-natally the infant was found to have a low birth weight, short birth length, contractures, short limbs, and a small thorax with upslanting ribs. Assisted ventilation and gastrostomy were required. At age 6 months, the infant required hospitalization for hypertrophic cardiomyopathy which responded to Atenolol. Initial cytogenetic studies demonstrated an apparently balanced de novo Robertsonian translocation involving chromosomes 14 and a karyotype designation of 45,XY,t(14q14q). No indication of mosaicism for trisomy 14 was observed in metaphase spreads prepared from peripheral blood lymphocytes or skin-derived fibroblasts. C-band and fluorescence in situ hybridization results demonstrated that the chromosome was dicentric. DNA analyses showed paternal uniparental isodisomy for chromosome 14. Based on the cytogenetic and DNA results a final karyotype designation of 45,XY,idic(14)(p11) was assigned to this infant with paternal isodisomy of chromosome 14.

Membranous nephropathy in two human leukocyte antigen-identical brothers.

We describe two Hispanic brothers with membranous nephropathy who had nephrotic syndrome in the first 2 years of life. Secondary causes of membranous nephropathy were excluded by clinical history and laboratory data. The occurrence of membranous nephropathy in these two young brothers, as well as in other familial cases reported to date, suggests an X-linked mode of inheritance.

Proximal 7q interstitial deletion in a severely mentally retarded and mildly abnormal infant.

We describe a boy with an interstitial deletion of 7q [46,XY,del(7)(pter-->q11.21::q11.23-->qter)] and severe mental retardation, bilateral inguinal hernias, plagiocephaly, and mildly abnormal facial appearance. This is the 21st case report involving a proximal 7q deletion, but the first report of this specific deletion in the absence of Zellweger syndrome. Specific genotype-phenotype correlations are still not possible for this region of chromosome 7.

Oculoauriculovertebral anomaly: segregation analysis.

Seventy-four families of probands with oculoauriculovertebral anomaly were evaluated, including 116 parents and 195 offspring. Relatives were examined to identify ear malformations, mandibular anomalies, and other craniofacial abnormalities. For segregation analysis using POINTER, selection of the sample was consistent with single ascertainment. Different population liabilities were used for probands and relatives, because affection was narrowly defined for probands and broadly defined for relatives. The hypothesis of no genetic transmission was rejected. The evidence favored autosomal dominant inheritance; recessive and polygenic models were not distinguishable.

Trisomy 8p: unusual origin detected by fluorescence in situ hybridization.

Chromosomal analysis of a neonate with brain and heart abnormalities revealed trisomy for 8p. The mother's karyotype showed 47 chromosomes with one chromosome 8 being represented as two separate chromosomes, an acrocentric 8p and a telocentric 8q. G-banding and silver staining revealed a satellite and nucleolus organizing region (NOR) on the 8p. Centromeric-specific probes to the centromeres of chromosomes 8, 15, 13/21, 22 and the acrocentric chromosomes revealed that only the 8q centromere was of chromosome-8 origin, while the 8p centromere was of chromosome-14 origin.

Progressive early dermatologic changes in Hutchinson-Gilford progeria syndrome.

We describe evolving dermatologic findings in a male with progeria from age 1 month to 21.5 months. At 18 months of age, irregular pigmentary changes of the abdomen, early occipital alopecia, superficial scalp veins, glyphic nasal tip, absent ear lobules, coarse hair that stands on end, crowded dentition with delayed tooth development, and dystrophic nails permitted the diagnosis of progeria. Radiographs showed evidence of resorption of the distal ends of the clavicles, attenuation of the terminal phalanges, diffuse osteopenia, and fishmouth vertebral bodies, which are typical of this syndrome. Appreciation of the evolution of early dermatologic findings may permit earlier diagnosis of this condition in infants with skin changes.

Microtia and associated anomalies: statistical analysis.

Terms such as oculoauriculovertebral dysplasia, Goldenhar syndrome, and hemifacial microsomia have been used to describe microtia with specific combinations of other craniofacial anomalies. Microtia is also observed with anomalies of postcranial structures. Statistical studies were performed on 297 patients with microtia and other anomalies to identify subgroups of patients representing previously described or new associations. Analysis identified 15 subgroups of patients with specific patterns of anomalies. Log-linear analyses of cranial and postcranial variables demonstrated a positive association between mandibular hypoplasia and cervical spine fusion, which was, in turn, positively associated with other spine anomalies (P less than .02) and other skeletal anomalies (P less than .001). Although unilateral microtia was commonly observed with mandibular hypoplasia, mandibular hypoplasia was negatively associated with bilateral microtia. Many of the associated anomalies were of structures not derived from the 1st and 2nd branchial arch neural crest. However, most associated anomalies were of structures derived from migratory cell populations or populations undergoing differentiation prior to migration between the 19th and 24th day post-fertilization (neural crest, ectodermal placode, mesoderm, surface ectoderm). These findings suggest that many different cell populations may be disturbed in the pathogenesis of microtia in association with other anomalies. The timing of the pathogenetic event may determine the specific pattern of associated anomalies.

Oculoauriculovertebral spectrum: an updated critique.

A comprehensive review and critical analysis of oculoauriculovertebral spectrum are provided. Topics discussed include nosologic problems, epidemiology, etiology (chromosomal, monogenic, teratogenic), and pathogenesis (hematoma formation, other vascular mechanisms, overripeness ovopathy). Clinical manifestations are thoroughly reviewed, updated, and documented for craniofacial features, central nervous system characteristics (including the wide spectrum of CNS malformations that make up the so-called "expanded Goldenhar complex"), congenital heart defects, and various other anomalies (kidney, lung, gastrointestinal tract). A number of conditions are discussed that are commonly differentiated from oculoauriculovertebral spectrum but have overlapping relationships, in some instances, with frontonasal dysplasia, branchio-oto-renal (BOR) syndrome, Townes-Brocks syndrome, Wildervanck syndrome, DiGeorge sequence, and several associations (VATER, CHARGE, and MURCS).