Management of rhesus isoimmunization by preimplantation genetic diagnosis

Intracranial osteolipomas are rare lesions which occur in the region of the tuber cinereum. All cases reported to date have been incidental autopsy findings. We describe a patient who presented with a variety of neurological symptoms and had a typical osteolipoma surgically removed.     

Application of single-needle blastomere biopsy in human preimplantation genetic diagnosis

We have tested and subsequently successfully applied a single-needle approach to obtain blastomere biopsies from human preimplantation embryos for preimplantation genetic diagnosis (PGD). The method was first evaluated in a mouse system and shown to be compatible with a high degree of in vitro and in vivo development of biopsied mouse embryos. Furthermore, we showed that biopsied mouse embryos after transfer to recipient mice underwent implantation, normal development and delivery. Litters were followed through puberty and adulthood and shown to be normal with regard to sexual function and also a panel of biochemical and morphological parameters including organ histology. Successful human preimplantation diagnosis, followed by pregnancies and birth of healthy babies, was established with two out of three couples carrying a risk to transmit chromosomal abnormalities leading to severe disease. This is the first report of the successful use of a single-needle approach in human PGD. Considering its simplicity, we conclude that the single-needle approach is an attractive alternative for biopsies in PGD.     

Taking a count: the evaluation of genetic testing

While some forms of genetic testing have been available for decades, the progress of the Human Genome Project will expand the possibilities for testing. Evaluation of genetic testing is warranted because health care services have an opportunity cost and thus the benefits of testing must be assessed against the costs. However, genetic testing raises new methodological difficulties in taking into account the full range of costs, benefits and risks. The conventional approach to evaluating new technologies is to assess their benefits in terms of health outcomes only, and to consider the effects on the individuals being tested. Like any test, the product of genetic testing is information. Any subsequent health outcome gain depends on the effectiveness of any intervention which results from the information. Assessing the benefits in terms of health outcomes only excludes consideration of any value, both positive and negative, attached to information. The special feature of genetic testing is that the information obtained has implications for family members. This information may have value to relatives individually and may affect family interactions. Information also has value at a social level; it may affect social relationships and interactions. As the possibilities for genetic testing expand, it is likely that testing programs will be subject to economic evaluation. Until the methods and measures used can validly take this range of effects into account (and into a count of benefits), then the results of evaluation studies will be, at best, incomplete and, at worst, misleading.     

Pharmacists' role in a smoking-cessation program at a managed health care organization

A smoking-cessation program at a managed health care organization and the involvement of pharmacists are described. Kaiser Permanente Northwest Region is a prepaid group-practice managed health care organization serving more than 380,000 members in Oregon and southwest Washington. A multidepartmental team at Northwest Region designed and implemented a stepped-care approach to smoking cessation in March 1992. The program progresses from advising and helping patients to quit on their own to enrolling patients in a behavioral-modification course to referring them to nicotine-replacement therapy to be given concurrently with the behavioral modification. The program was established with the help of pharmacists, and pharmacists are deeply involved in its operation. They work closely with each patient, the health educator instructing the patient, and the prescribing physician. Pharmacists attend 5 of the 10 behavioral modification/nicotine-replacement course sessions and take responsibility for enrollees throughout the program. Pharmacists prescribe and monitor nicotine-replacement therapy by protocol. They also monitor each patient for the dose-response effect, adverse drug reactions, drug interactions, concurrent medical conditions, and progress and outcome. The physician is informed about any important changes in the patient's status. In 1992, more than 80 courses were held with nearly 1000 participants, and rates of long-term abstinence achieved compare favorably with literature rates for community-based group smoking-cessation programs. Satisfaction of patients, pharmacists, and physicians with the program has been high. Pharmacists at a managed health care organization participate in a smoking-cessation program by helping with behavioral modification, educating patients about nicotine-replacement therapy, and prescribing and monitoring therapy by protocol.     

Improving the fixation method for preimplantation genetic diagnosis by fluorescent in situ hybridization

The function of the hypothalamic-pituitary-adrenal axis as related to the degree of severity of a septic process was assessed by measuring plasma levels of beta-endorphin, ACTH and cortisol. Sixty-one cases of postoperative patients treated at the intensive care unit were classified into four groups according to the severity of infection: Group 1 (control) included patients who did not show any sign of infection, group 2 patients with sepsis, group 3 patients with septic syndrome and group 4 patients with septic shock. Compared to G1 patients' ACTH values (4.16+/-2.6pg/ml), a statistically significant increase in ACTH values in various stages of septicemia (p < 0.005) with a noticeable difference also between G3 (7.11 +/-3.7pg/ml) and G4 (11.5+/-6.6pg/ml) (p<0.05) was found. Differences were also observed in beta-endorphin (with a level of significance between the several groups of p = 0.0001). Also, beta-endorphin values in G4 (40.6+/-30.3 pg/ml) differed significantly from each of G1 (17.5 +/-6.6 pg/ml), G2 (21.1+/-11.3 pg/ml) and G3 (23.5+/-12 pg/ ml) (p<0.05). A progressive hypercortisolemia was obvious, with values of G4 (37.2+/-15.6 microg/dl) differing significantly from those of G1 (18+/-4.6microg/dl) and G2 (24-/+8.4microg/dl) (p<0.05) and of G3 (28.5+/-12.3 microg/dl) from that of G1 (p < 0.05). Interestingly, a dissociation of ACTH, beta-endorphin and cortisol was observed, in that the increased values of beta-endorphin and cortisol, detected in the G3 were not associated with a parallel increase in ACTH. These findings might be interpreted in the sense of an impairment of the stress stimulation of the hypothalamic pituitary adrenal axis. Provided that such a situation can be lethal, our results further confirm the idea that a low-dose, steroid replacement might be beneficial to critical illness.     

Chromosome translocations: segregation modes and strategies for preimplantation genetic diagnosis

Preimplantation genetic diagnosis (PGD) offers polymerase chain reaction tests for an increasing range of single gene defects, and fluorescence in situ hybridization tests for sex determination (for X-linked conditions) and for aneuploidy detection. Patients carrying chromosome translocations with a high reproductive risk are increasingly seeking to increase their chances of a normal pregnancy with the help of PGD, for which they present a special challenge. This paper describes the behaviour of reciprocal translocations at meiosis, discusses current methods of detecting meiotic outcomes at the preimplantation stage and outlines ways forward for preimplantation diagnosis of these common rearrangements. We also propose a more general strategy using recently developed chromosome-specific sub-telomeric probes, combined, if possible, with proximal probes, to form a strong diagnostic tool.     

Pregnancy after preimplantation genetic diagnosis for Charcot-Marie-Tooth disease type 1A

Charcot-Marie-Tooth (CMT) disease type 1A is an autosomal dominant peripheral neuropathy characterized by slow progressive distal muscle wasting and weakness, and decreased nerve conduction velocities. Most CMT1A cases (>98%) are caused by a duplication of a 1.5 Mb region on the short arm of chromosome 17 containing the PMP22 gene. A couple with a previous history of CMT followed by termination of pregnancy was referred to our centre for preimplantation genetic diagnosis (PGD). The husband carries the CMT1A duplication which can be detected by polymerase chain reaction (PCR) analysis using polymorphic (CA)n markers localized within the duplication. PCR amplification of genomic DNA of the parents-to-be with one of the two primers labelled with fluorescein, followed by automated laser fluorescence (ALF) gel electrophoresis of the amplified fragments allows the distinction between both genotypes. Embryos obtained after intracytoplasmic sperm injection (ICSI) were evaluated for the presence of the normal allele of the father. PCR with single Epstein-Barr virus-transformed lymphoblasts and blastomeres resulted in 91.4 and 93.5% amplification efficiency respectively, whereas none of the blank controls gave a positive signal. Allele drop-out (ADO) was observed in eight out of 32 lymphoblasts (25%) or in five out of 21 blastomeres (23.8%). However, within this set-up ADO will never lead to transfer of an affected embryo. A first ICSI-PGD cycle did not result in embryo transfer for the patient. A second cycle involved 10 mature oocytes of which eight were fertilized, resulting in five embryos for biopsy. Two unaffected embryos were available for transfer and resulted in a singleton pregnancy. The genotype of the fetus has been confirmed healthy by chorionic villus sampling.     

Attitude of potential users in Sicily towards preimplantation genetic diagnosis for beta-thalassaemia and aneuploidies

This study aims to report the willingness of different populations of high-risk couples to undergo preimplantation genetic diagnosis (PGD) for beta-thalassaemia as an alternative to prenatal genetic diagnosis (PND), and the willingness of infertile couples to undergo PGD for aneuploidies. An information sheet and questionnaire presenting PGD and PND procedures were distributed to four population types: 54 high-risk couples for beta-thalassaemia coming for their first PND (population A); 51 similar couples coming for their second or further PND without previous experience of therapeutic abortion (population B-na); 50 similar couples coming for their second or further PND with previous experience of therapeutic abortion for beta-thalassaemia-affected fetus (population B-ab); and 74 infertile couples undergoing routine in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) (population C). Favourable first impressions towards PGD compared with PND were observed in all four populations in the following proportions: 79.6% population A; 76.5% population B-na; 92.0% population B-ab; and 96.0% population C. Willingness to undergo PGD for beta-thalassaemia was as follows: 44.4% population A; 47.1% population B-na; and 72.0% population B-ab. We conclude that previous experience of PND for beta-thalassaemia is a crucial point in the willingness to accept the PGD procedure, and that couples belonging to population B-ab are the most suitable to undergo PGD for beta-thalassaemia. Some 96.0% of infertile couples in population C were ready to undergo PGD for aneuploidies.     

Preimplantation genetic testing for Marfan syndrome

Marfan syndrome (MFS) is an autosomal dominant disease that affects the skeletal, ocular and cardiovascular systems. Defects in the gene that codes for fibrillin (FBN-1) are responsible for MFS. Here we report the world's first use of preimplantation genetic testing (PGT) to achieve a clinical pregnancy and live birth of a baby free of a Marfan mutation. One or two blastomeres from each embryo were tested for a CA repeat within the FBN-1 gene. The prospective mother is homozygous for the CA repeat (2/2) and has two normal copies of the FBN-1 gene, while the prospective father is heterozygous for the CA repeat (1/2), and is affected with the Marfan syndrome. In the father's family, allele 2 segregates with the mutated FBN-1 gene. For PGT, any embryo diagnosed as heterozygous for the CA repeat (1/2) would be presumed to have inherited normal FBN-1 genes from the father and the mother and be unaffected. One in-vitro fertilization (IVF) cycle yielded 12 embryos for preimplantation testing; six of the embryos were heterozygous for the CA repeat (1/2) and presumed to be free of the Marfan mutation. Five of the six embryos were subsequently transferred into the uterus. The fetus was tested by chorionic villus sampling and found to be free of the Marfan mutation by the same linkage analysis, had a normal fetal echocardiogram, and was normal at birth.     

The case against preadoption genetic testing

Adoption professionals and prospective adoptive families have become increasingly interested in obtaining genetic information on children prior to adoption. Predictive genetic testing of apparently healthy children has been urged as a way of generating information about children's future health and assisting families in deciding whether to adopt. Such genetic testing of children, however, raises a host of ethical issues with important implications for adoption policy and practice. The medical and psychosocial benefits and risks of predictive testing provide the context for analyzing the ethics of such testing. Ethical considerations strongly counsel against predictive genetic testing solely for purposes of evaluating a child for adoption.