Involvement of the mitogen-activated protein kinase cascade in peroxynitrite-mediated arachidonic acid release in vascular smooth muscle cells.

Eicosanoid production is reduced when the nitric oxide (NO.) pathway is inhibited or when the inducible NO synthase gene is deleted, indicating that the NO. and arachidonic acid pathways are linked.

Maternal 3;13 chromosome insertion, with severe pre-eclampsia.

A previously healthy young primigravida suffered very severe pre-eclampsia and was delivered at 32 weeks gestation. The baby was growth retarded with dysmorphic features, and died aged 4 days. Chromosome analysis of the baby revealed partial trisomy 13 resulting from recombination within a maternal insertion of part of 13q into 3p.

Prenatal testosterone levels in XXY and XYY males.

It has been postulated that behavioural differences between normal males and those with an additional X or Y chromosome may be related to pre- or postnatal hormonal variations. The prenatal hormone status was investigated using amniotic fluid obtained at antenatal diagnosis between 16 and 20 weeks gestation from fetuses with sex chromosome abnormalities and from controls of the same gestational age. After log transformation, the (geometric) mean testosterone levels were XY 439.

Molecular studies of trisomy 18.

We have determined the parental origin of 50 cases of trisomy 18. In 48 cases the additional chromosome was maternal in origin, and in 2 cases it was paternal in origin. Seven cases, including both those with an additional paternal chromosome, appeared to be the result of postzygotic error.

Direct diagnosis of myotonic dystrophy with a disease-specific DNA marker.

Background: Myotonic dystrophy is the most common inherited form of muscular dystrophy affecting adults. Its symptoms are not confined to muscle, and variability in their nature and in the patient's age at their onset can make diagnosis difficult. A specific unstable DNA sequence associated with myotonic dystrophy has recently been identified.

Long term effects of periconceptional multivitamin supplements for prevention of neural tube defects: a seven to 10 year follow up.

Periconceptional supplementation with Pregnavite Forte F was offered to women who presented consecutively to the Oxford genetic counselling service in the early 1980s who had previously had one or more pregnancies complicated by a neural tube defect. The first 100 children born alive to these women are the subject of this study. Birth weight, gestation, and congenital abnormalities were recorded.

Molecular studies of the fragile X syndrome.

We have studied families segregating for the fragile X syndrome for the presence of amplification of the CGG repeat sequence adjacent to the HpaII Tiny Fragment (HTF) island in the FMR-1 gene. We demonstrate that 138/143 fragile X positive, mentally retarded males show a characteristic smear of fragments corresponding to somatic variation in the amplification of the CGG sequence. In 7/8 normal transmitting males (NTM's), we show that there is a small amplification of sequence but no evidence for somatic variation.

UK clinicians' knowledge of and attitudes to the prenatal diagnosis of single gene disorders.

Postal questionnaires were sent to 308 clinicians in the UK (general practitioners, obstetricians, clinical geneticists, neurologists, paediatricians, and paediatric neurologists) to assess their knowledge of, and attitudes to, the prenatal diagnosis of three common single gene disorders, Huntington's disease (HD), cystic fibrosis (CF), and Duchenne muscular dystrophy (DMD). Replies received numbered 213, a response rate of 69%. Overall, 95% of responding clinicians thought that offering prenatal diagnosis for the three test conditions was often or always appropriate.

Interstitial deletion of the long arm of chromosome 18, del(18)(q12.2q21.1): a report of three cases of an autosomal deletion with a mild phenotype.

We describe three unrelated patients with apparently identical interstitial deletions of the segment (18) (q12.2q21.1).

Severe limb abnormalities after chorion villus sampling at 56-66 days' gestation.

Among 289 pregnancies in which chorion villus sampling (CVS) was carried out at 56-66 days' gestation, 5 babies with severe limb abnormalities were subsequently identified. 4 had oromandibular-limb hypogenesis syndromes, and the other had a terminal transverse limb reduction defect. This high incidence raises the possibility that CVS was an aetiological factor for these developmental anomalies.

Ankyloblepharon filiforme adnatum in trisomy 18 Edwards syndrome.

Three cases of ankyloblepharon filiforme adnatum (AFA) in infants with Edwards syndrome are described. The case for a fifth subgroup of AFA is reinforced.

Investigation of three patients with the "ring syndrome", including familial transmission of ring 5, and estimation of reproductive risks.

We report three cases of ring chromosome 5 [r(5)], two familial (mother and daughter) and one sporadic. The phenotype resembled that of the "ring syndrome" with prenatal onset of short stature, growth retardation, mild facial dysmorphism and normal psychomotor development. Extended metaphase and prometaphase chromosome preparations using G-, R- and Q-banding and scanning electron microscopy (SEM) failed to demonstrate deletion in the ring 5.

Prevalence of Huntington's disease among UK immigrants from the Indian subcontinent.

Using the records of Churchill Hospital, Oxford, and those of genetics centres and other national institutions, the minimum prevalence of HD among immigrants from the Indian subcontinent was found to be almost half that found in the indigenous UK population. However, this observed prevalence was probably depressed, and therefore may not differ greatly from that estimated for European populations. All the identified cases were immigrants from Pakistan, the Punjab and Gujerat; none were from Bangladesh.

Neocerebellar hypoplasia in a neonate following intra-uterine exposure to anticonvulsants.

An infant with dysmorphic features was born to an epileptic mother who had taken phenytoin and sodium valproate throughout pregnancy. The infant began to have intractable seizures 10 minutes after delivery, and retrospective reports from the mother suggested they may have occurred in utero. Ultrasound examination of the brain showed a very wide subarachnoid space and CT confirmed cerebral and cerebellar underdevelopment.

Clinical features and molecular analysis of the alpha thalassemia/mental retardation syndromes. II. Cases without detectable abnormality of the alpha globin complex.

We have identified five unrelated patients, all of north European origin, who have hemoglobin H (Hb H) disease and profound mental handicap. Surprisingly, detailed molecular analysis of the alpha globin complex is normal in these subjects. Clinically, they present with a rather uniform constellation of abnormalities, notably severe mental handicap, microcephaly, relative hypertelorism, unusual facies and genital anomalies.

Clinical features and molecular analysis of the alpha thalassemia/mental retardation syndromes. I. Cases due to deletions involving chromosome band 16p13.3.

We describe eight patients who have alpha thalassemia which cannot be accounted for by the Mendelian inheritance of abnormal alpha globin genes. Apart from the hematologic abnormality, the other universal clinical finding is mild to moderate mental handicap; there is also a broad spectrum of associated dysmorphic features. Initial analysis of the alpha globin gene complex (which maps to chromosome band 16p13.

Oral fibromatosis in tuberous sclerosis.

Thirty-six families with tuberous sclerosis (TS) were clinically examined for oral fibromatosis and other previously reported oral anomalies. These consisted of 48 affected persons and 69 apparently unaffected parents and children. Fifty control subjects were also examined.

Detection of breakpoints in submicroscopic chromosomal translocation, illustrating an important mechanism for genetic disease.

A 3-year-old boy presented with alpha-thalassaemia, dysmorphic features, and mental handicap. His younger sister is also mentally retarded, but haematologically normal. High resolution cytogenetic analysis revealed a normal karyotype in all family members.

The nature of the defect in cobalamin G mutation.

Cobalamin G mutation (cblG) typically presents as a severe megaloblastic anemia during the first few weeks of life. The anemia responds completely to treatment with high doses of Cbl but the neurologic manifestations respond more slowly and not always completely. Cultured fibroblasts from two affected infants and virus-transformed lymphoblasts from one of the infants expressed the following: poor growth in the absence of methionine, the ability to take up and internalize Cbl bound to transcobalamin II, impaired synthesis of methionine from homocysteine, the ability to bind incoming Cbl to the respective coenzymes, but an inability to synthesize methylcobalamin in spite of a normal capacity to synthesize adenosylcobalamin.

Fraser syndrome (cryptophthalmos-syndactyly syndrome): a review of eleven cases with postmortem findings.

Detailed postmortem findings from 11 cases of probable Fraser (cryptophthalmos-syndactyly) syndrome are reported. Eight cases presented as neonatal deaths, one as a stillbirth, and there were 2 midtrimester fetuses. All of the cases had ocular, otic, digital, laryngeal, and renal abnormalities.