Baruch Brooks

Chromium and Cholesterol-Induced Atherosclerosis in Rabbits

Thirty-three rabbits on a cholesterol-enriched diet were randomized into 6 groups and treated with daily injections of either water, 20 micrograms of potassium chromate or 1, 5, 10 or 20 micrograms of chromium chloride, respectively, for 135 days with a 2- to 10-fold increase in serum chromium. There was a marked reduction in the percentage of aortic intimal surface covered by plaque, in aortic weight and cholesterol content in the treated animals. Rabbits treated with 20 micrograms of chromium chloride showed a better response than those treated with either 10 or 20 micrograms of potassium chromate.

PGD for fragile X syndrome: ovarian function is the main determinant of success

BACKGROUND PGD for fragile X syndrome (FRAX) is inefficient, probably owing to fewer oocytes, poor embryo quality and difficulties in genetic analysis. We investigated IVF-PGD in FRAX mutation carriers compared with controls, looking at the effects of oocyte and embryo number/quality on live birth outcome. METHODS We performed IVF-PGD in 27 patients with the FRAX mutation and 33 controls with other genetic diseases. Genetic testing was by multiplex PCR. RESULTS Seventy-nine and 108 IVF-PGD cycles were started in FRAX mutation carriers and controls, respectively. Twenty-two patients had a premutation (CGG repeat number 60-200) and five had a full mutation (300-2000 CGG repeats). FRAX patients required higher doses of gonadotrophins (6788 ± 2379 versus 4360 ± 2330, P< 0.001) but had lower peak serum estradiol levels (8166 ± 5880 versus 10 211 ± 4673, P = 0.03) and fewer oocytes retrieved (9.8 ± 6 versus 14 ± 8, P = 0.01). The cancellation rate (unsatisfactory ovarian response) was higher in the FRAX group than in the control group (13 versus 1%, P < 0.001). When embryos were transferred, ongoing pregnancy/live birth rates per transfer were similar (29 versus 36%, P = 0.54). CONCLUSIONS Ovarian dysfunction in FRAX carriers is more prevalent and profound than previously appreciated, with a high cancelation rate and reduced efficiency of PGD. The main determinant for successful PGD for FRAX is ovarian dysfunction. When embryo transfer is possible, the results are comparable to PGD for other monogenic diseases.

Preimplantation genetic diagnosis (PGD)--prevention of the birth of children affected with endocrine diseases.

Abstract Objective: To develop a reliable and accurate preimplantation genetic diagnosis (PGD) method in six families with endocrine diseases: persistent hyperinsulinemic hypoglycemia of infancy (PHHI), congenital adrenal hyperplasia (CAH) salt-wasting form, Sanjat-Sakati syndrome and multiple endocrine neoplasia 2A (MEN 2A). Methods: For each disease a battery of at least four informative markers surrounding the tested gene were identified and for each family a protocol of multiplex fluorescent markers was developed and performed on single cells. Results: PGD for PHHI was performed in three families. In family 1 two healthy children were born from different cycles, in family 2 three healthy children were born from two cycles, and in family 3 a healthy boy was born. For CAH in one family a healthy girl was born. One PGD cycle for Sanjat-Sakati resulted in a clinical pregnancy that was terminated due to high nuccal translucency (46X0). For one family with MEN 2A disease, the eighth PGD cycle resulted in birth of healthy twins. In all children genetic confirmation of the healthy status was performed. Conclusions: PGD is an effective method for preventing birth of affected children with endocrine disorders. Increasing the awareness of clinicians to the availability of these methods is most important.

Preventing mucopolysaccharidosis type II (Hunter syndrome): PGD and establishing a Hunter (46, XX) stem cell line

Preimplantation genetic diagnosis (PGD) enables the identification of affected embryos prior to implantation. We present for the first time three families in which either the oocytes or embryos obtained from female carriers of mutations in the iduronate‐2‐sulfatase (IDS) gene underwent PGD for mucopolysaccharidosis type II (Hunter syndrome). Furthermore, we report the first ever derivation of a Hunters syndrome (46, XX) human stem cell line from embryos (HESC) carrying the IDS and oculocutaneus albinism type 2 mutations.

Transfer of embryos from yeast-colonized dishes

OBJECTIVE To report yeast colonization in IVF dishes, where ET was carried out, and the IVF outcome was not compromised. DESIGN Retrospective study of patients who underwent IVF cycle during the last 4 years. SETTING In vitro fertilization program at the Shaare-Zedek hospital in Jerusalem. PATIENTS Five couples who underwent standard IVF cycles and whose dishes were colonized with yeast. After thorough discussion ET was carried out. RESULTS Although colonized with yeast, the quality of the embryos was not compromised. One to three of these embryos were transferred. All five women conceived. CONCLUSIONS In vitro fertilization outcome is not necessarily compromised by yeast colonization. Nevertheless, the possible teratogenic effect of yeast on embryos has not been investigated and research is required to address this concern.

Elevated serum progesterone levels during pituitary suppression may signify adrenal hyperandrogenism

OBJECTIVE To investigate whether elevated serum P levels after pituitary down-regulation signify adrenal enzyme defects or hyperandrogenism. DESIGN Prospective study. SETTING Assisted reproduction unit in a university medical center. PATIENT(S) Two hundred twenty-seven IVF patients treated by the long down-regulation protocol. INTERVENTION(S) Oral dexamethasone (DEX) administration if P level exceeded 0.8 ng/mL (conversion factor to SI unit, 3.180) after pituitary suppression. MAIN OUTCOME MEASURE(S) Serum concentrations of P, E2, LH, DHEAS, and 17 alpha-hydroxyprogesterone and ACTH stimulation tests. RESULT(S) In eight patients (3.5%), serum P levels exceeded 0.8 ng/mL and E2 and LH levels confirmed pituitary down-regulation. Mean DHEAS levels in the patients in this group were significantly higher than in the other patients. All eight patients demonstrated a significant decrease in serum P level after DEX administration. In five patients the ACTH stimulation test suggested an adrenal defect. Five pregnancies were achieved after the addition of DEX to the treatment protocol. CONCLUSION(S) High serum P levels after pituitary down-regulation appear to be of adrenal origin and may be the first indication of an adrenal enzyme defect. Further investigation such as an ACTH stimulation test is recommended, followed by treatment with DEX if indicated.

Polar Body-Based Preimplantation Genetic Diagnosis for N-Acetylglutamate Synthase Deficiency

Objective: We describe a sensitive and highly reliable preimplantation genetic diagnosis (PGD) assay for N-acetylglutamate synthetase (NAGS) deficiency using polar body (PB) analysis in conjunction with multiple markers flanking the gene. This rare autosomal recessive mitochondrial disorder is characterized by hyperammonemia, uncontrollable movements, developmental delay, visual impairment, failure to thrive and vomiting and is caused by mutations in the NAGS gene located on chromosome 17q21.31. Methods: For a family with an affected child we have developed a multiplex fluorescent PCR protocol that included detection of the specific familial mutation (2729insC) in conjunction with the analysis of five informative polymorphic markers flanking the gene: D17S902, D17S965, D17S1861, D17S791 and D17S1868. Following successful amplification in single-cell fibroblasts, this protocol was used in the couple carriers of NAGS mutation. Results: Of 18 retrieved eggs, 16 were at the M2 stage and 9 fertilized. 12 polar body 1s (PB1) were heterozygotes, 1 homozygote wild-type, 1 total amplification failure, and two showed inconclusive results. Three oocytes that had heterozygote PB1s showed mutant polar body 2 (PB2) indicating a wild-type oocyte. Despite the fact that the specific 2729insC mutation did not amplify in the PGD cycle, analysis of linked markers in PBs was sufficient to ensure an accurate diagnosis in 5 out of 9 oocytes. This cycle resulted in the transfer of 3 embryos originating from oocytes diagnosed as wild-type by PB analysis, with the subsequent birth of healthy twin girls. Postnatal genetic testing revealed that both girls harbored the healthy maternal allele and carried the mutant paternal allele. Conclusions: Our multiplex-nested PCR protocol based on several linked microsatellite markers offers an efficient and accurate method for PGD for NAGS syndrome even when the mutation is not amplified.

A routine method for the measurement of the sodium, potassium, magnesium and calcium content of human lymphocytes

We describe a rapid, single-step procedure for the isolation of human lymphocytes from whole blood, suitable for a routine clinical laboratory. Lymphocyte content of sodium, potassium, magnesium and calcium were measured simultaneously in a group of controls and found to fall within expected ranges. Expression of results per mg protein produced less inter-individual variation than per unit cell. In order to examine another, physiologically different but normal population, women during pregnancy were also studied. The cation content of lymphocytes expressed per mg protein was significantly lower than for controls due to a 44% increase in protein content per cell.

Preimplantation Genetic Diagnosis in Genomic Regions with Duplications and Pseudogenes: Long‐Range PCR in the Single‐Cell Assay

Long‐range PCR is generally employed for the analysis of disease‐causing mutations in genes with homologous pseudogene copies. However, long‐range PCR is challenging when performed on single cells, as in preimplantation genetic diagnosis (PGD) of monogenic disorders. PGD on single cells requires concurrent analysis of a mutation together with multiple linked polymorphic markers from closely related family members to prevent misdiagnosis. In PGD cases involving childless de novo mutation carriers, linkage cannot be performed based on family members but rather must first be identified in single gametes. This can be an especially difficult task if the mutation to be assayed lies in a duplicated genomic region because gene‐specific long‐range PCR must be coupled with short‐range PCR analysis of genetic markers on single cells. Here, we describe a novel method by which accurate PGD of pseudogene‐homologous mutations can be achieved. Essentially, we performed whole genome amplification on single sperm or blastomeres followed by haplotype construction and long‐range PCR‐based mutation analysis. This original and universal strategy was used to establish allelic association for two different mutations in genes with one or more pseudogene copies (IKBKG and PKD1). The method was also sensitive enough to detect unexpected germline mosaicism in one mutation carrier.

Preimplantation genetic diagnosis (PGD) for a treatable disorder: Gaucher disease type 1 as a model

BACKGROUND Preimplantation genetic diagnosis (PGD) is a technique that enables identification of unaffected embryos prior to in vitro fertilization (IVF) transfer in couples at risk for a Mendelian disorder. Most cases involve severe genetic diseases with neurological features and/or major malformations. We present two couples in which PGD was performed for prevention of type 1 Gaucher disease, a non-neuronopathic, non-lethal disorder. MATERIALS AND METHODS We developed a multiplex fluorescent PCR protocol, simultaneously amplifying the familial mutations and eight closely spaced, highly polymorphic informative microsatellite markers surrounding the gene, to be used for PGD analysis. RESULTS Couple #1 mother was homozygous for the N370S mutation and the father carried the 84GG mutation; their first daughter receives specific Gaucher therapy. One PGD cycle resulted in seven embryos of which four had the paternal wild type allele; two were transferred resulting in a healthy baby boy born at term. Couple #2, each a carrier (N370S and R359Q), whose first-born child had died (age 5years) of Gaucher disease, underwent 7 PGD cycles. Only one cycle resulted in a clinical pregnancy but a miscarriage was followed at 10weeks. CONCLUSIONS PGD is an effective and accurate method for preventing Gaucher disease type I in carrier couples. Since this disease is treatable, special ethical considerations and careful selection of couples should be performed.