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J Feingold

Publications and source records attributed to J Feingold.

At least 163 records · Page 9Linked to original sources
PubMed1986

Some trends in medical populations genetics.

Five topics concerning medical population genetics have been selected for discussion: in the field of population cytogenetics, the frequency of chromosomal aberrations and the roles of mutation and selection in the maintenance of balanced rearrangements are studied; the long term genetic effects of treatment and prevention of genetic diseases are reviewed; the relationships between malaria and the sickle-cell trait are discussed; some recent works concerning human DNA polymorphisms in the field of population genetics are presented, and finally, some methods of genetic epidemiology are described.

Anemia, Sickle Cell↗
PubMed1986

Transcription initiation in vitro and in vivo at a highly conserved promoter within a 16 S ribosomal RNA gene.

Transcription initiation has been shown to occur in vitro at several sites within a cloned Caulobacter crescentus ribosomal RNA gene cluster that lacks the major promoter region 5' to the 16 S rRNA gene. The predominant transcription start site in vitro was located near the 3' end of the 16 S rRNA gene. Transcription initiation from this region was also detected in vivo, when the cloned rRNA gene cluster was present on a multi-copy plasmid. The transcription start sites in vitro and in vivo were shown to be identical by S1 nuclease mapping and were found to be located approximately 300 nucleotides upstream from the 3' end of the 16 S rRNA gene. The transcript synthesized in vitro was shown to be cleaved by C. crescentus RNase III and to release the transfer RNA genes from the downstream 16 S/23 S intergenic spacer region. Analysis of the nucleotide sequence near the internal 16 S rRNA transcription start site revealed the presence of a consensus promoter sequence followed by the beginning of an open reading frame approximately 90 nucleotides downstream. Examination of the 16 S rRNA genes from other bacterial species and chloroplasts and 18 S rRNA genes from Xenopus and yeast revealed that the nucleotide sequence of this internal 16 S rRNA promoter region was highly conserved. Although the length of these 16 S and 18 S rRNA genes is slightly variable, the distance of the conserved promoter sequence from the 3' end of these genes has been conserved.

Base Sequence↗
PubMed1986

Hemoglobin abnormalities. An evaluation on new-born infants and their mothers in a maternity unit close to Brazzaville (P.R. Congo).

In order to evaluate the polymorphism of hemoglobin in a population of Equatorial Africa, we undertook a prospective study of 146 births at a rural maternity hospital close to Brazzaville (P.R. Congo). This showed among the mothers 31 (22%) carriers of the sickle cell trait (AS), six with delta mutation, and two with beta-thalassemia trait. Among the children, 27 (18.5%) had sickle cell trait and one had sickle cell homozygosity. The frequency of the HbF Sardinia trait was 7.5%. This and other studies suggested a dilution gradient from Europe to Africa. Hemoglobin Bart's could be visually detected in 23.3% of the new-born babies. We attempted to distinguish between those infants with a high level of Hb Bart's (Bart's ++ group: 13.7%) and a group with a detectable Hb Bart's level that in our experimental conditions is between 1 and 2% (Bart's + group: 9.6%). Mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were 88.6 +/- 5.7 fl and 29.0 +/- 2.1 pg in the Bart's ++ group; 94.5 +/- 10.9 fl and 30.6 +/- 4.1 pg in the Bart's + group; whereas they were 101.0 +/- 8.7 fl and 33.9 +/- 2.5 pg in the control group. Since iron deficiencies are very rare in new-borns and selecting according to published data on black people as homozygous alpha-thalassemia of the type I (-alpha/-alpha), individuals of the Bart's ++ group whose MCV was below 95 fl and MCV below 30 pg, the gene frequency is estimated to be 34% and that of heterozygotes (-alpha/alpha alpha) 45%. These high frequencies were confirmed in AS mothers: 45% showed a significant decrease of the S fraction.

Adult↗
PubMed1986

Spirometric findings in capacitor workers occupationally exposed to polychlorinated biphenyls (PCBs).

Spirometric findings (forced vital capacity [FVC], forced expiratory volume at one second [FEV1], FEV1/FVC) in a population of capacitor workers with occupational exposure to polychlorinated biphenyls (PCBs) are described during active PCB use (1976) and following the PCB ban (1979 and 1983). The initial finding of restrictive impairment (16%) in 1976 was not supported by chest roentgenogram findings, nor confirmed in 1979 and 1983, and was interpreted as artifactual due to test operator inexperience and inadequate expiratory efforts. Obstructive impairment was consistently found in 15% of the total population in 1976 and 1979. A history of respiratory illness and/or symptomatology and reduced FEV1/FVC was correlated with PCB exposure and serum PCB levels (lower homologs) in females in 1976, but not in males. Smoking was correlated with reduced FEV1 values. No correlation of spirometric variables with past exposure or serum PCB levels was found for either sex in 1979.

Adult↗
PubMed1986

Genetic control of the proportion of gamma chains of human fetal haemoglobin.

The relative proportions of gamma chains of human fetal haemoglobin G gamma, A gamma 75 Ileu (A gamma I) and A gamma 75 Thr (A gamma T) were investigated in homogeneous populations of patients in Algeria exhibiting sickle cell disease and in patients in Algeria and Sardinia with beta-thalassaemia. The restriction site haplotypes within the beta gene cluster were known. The results suggest a tight genetic regulation of the G gamma/A gamma + G gamma ratio (G gamma ratio) which is associated with the G gamma Hind III site of polymorphism (p less than 0.0001). From the present results and those in the literature the high G gamma ratio is associated with the presence of 3 polymorphic restriction sites: Xmn1 5' to the G gamma gene, Hind III in the G gamma IVS II and Hinc II in the psi beta gene. Familial studies showed that the expression of the A gamma alleles is genetically determined. The wide variation of the A gamma T/A gamma T + A gamma I ratio (A gamma ratio) between families is most probably related to the various haplotypes bearing the A gamma I alleles.

Algeria↗
PubMed1986

[HLA antigens and different clinical forms of 21-hydroxylase deficiency in the French population].

HLA associations with 21-OH deficiency were studied on respectively 109 and 60 congenital and late onset French index cases. Significant negative associations were found with antigens B8: congenital forms; B5, DR3: late onset. Significant positive associations were observed with A3, Bw47 (A3 Cw6 Bw47 DR7): congenital forms; B40: salt-wasting form; B5: simple virilizing form; Aw33, B14, DR1, DR2, DRw6 (Aw33 B14 DR1): late onset form. Among late onset patients not bearing B14 antigens significant positive associations were observed with B12 and B35.

Adrenal Hyperplasia, Congenital↗
PubMed1986

[Rate of germinal mutation in man. Measurement and surveillance].

Estimate of the rate of germinal mutation in Man is difficult. Genic and chromosomic mutations must be considered separately. The only usable method, to avaluated the rates of genic mutation, is the direct method. The rate is estimated from the recording, at birth, of subjects with a particular phenotype due to a recent mutation, i.e. whose parents are normal. This mutation must be dominant with complete penetrance. In most of the cases, it is a dominant disease but a biochemical marker may also be used. This is a difficult method since there are many subjects to study and diagnosis errors are possible and the paternity is not always known. The rate of mutation of chromosomal aberrations may also measured. If we consider abnormalities of number, one has to know that the greatest majority results in early miscarriage; on the contrary, abnormalities of balanced structures are their detection is long and costly. The study of the variations of the mutation rate is, for those reasons, difficult. Methods of sequential analysis using "sentinel" phenotypes have factors which may modify the mutation rates are concerned, the effects of radiation are better known than those of chemical mutations in Man.

Biometry↗
PubMed1985

Genetic heterogeneity of Alport syndrome.

Forty-one families have been studied with stringent diagnostic criteria of Alport syndrome: proven renal disease with hematuria affecting at least two relatives, neural hearing loss in at least one affected individual, and evolution to renal failure in at least one affected individual. The proportion of affected offsprings of affected females does not significantly differ from the ratio expected for a dominant trait. The descendance of affected males shows a lack of affected males. In four families, with parental consanguinity and nonaffected parents, the findings agree with an autosomal recessive inheritance. Study of quantitative traits such as death or renal death among brothers, uncle-nephew pairs and whole families shows evident intra-familial resemblances. We conclude that Alport syndrome seems to be a heterogeneous state composed of a number of genetically distinct syndromes, with an autosomal dominant, an X-linked dominant, and an autosomal recessive form.

Consanguinity↗
PubMed1985

Organization and nucleotide sequence analysis of an rRNA and tRNA gene cluster from Caulobacter crescentus.

rRNA genes of Caulobacter crescentus CB13 were isolated and shown to be present in two gene clusters in the genome. The organization of each rRNA gene cluster was found to be 5'-16S-tRNA spacer-23S-5S-3'. The DNA sequence of 40% of the 16S rRNA gene, the entire 16S/23S intergenic spacer region, and portions of the 23S rRNA gene were determined. Analysis of the nucleotide sequence in the 16S-23S intergenic spacer region revealed the presence of tRNAIle and tRNAAla genes. Large invert repeat sequences were found surrounding the 16S rRNA gene. These inverted repeat sequences are analogous to the RNase III-processing sites in the E. coli rRNA precursor. Small invert repeat sequences were also found flanking the individual tRNA genes. RNA polymerase-binding studies with restriction fragments of the rRNA gene cluster revealed three regions which bound enzyme, and these regions were shown to contain transcription initiation sites. One of these sites was located within the 16S gene near its 3' end, and the other two were found at the 5' end of the 23S gene.

Base Sequence↗
PubMed1985

Effects of PCB exposure on biochemical and hematological findings in capacitor workers.

Certain former operations in capacitor manufacturing resulted in extensive direct contact of the workers with electrical grade polychlorinated biphenyls (PCBs). A study group of 194 such individuals, all exposed to Aroclor 1016 and many previously exposed to Aroclors 1242 and/or 1254, was examined before (1976) and after (1979) discontinuance of PCB use in the operations (1977). At the two examinations, the approximate geometric mean serum levels (in ppb) and 5 to 95% ranges were for lower PCBs (LPCB), 363 (57-2270) and 68 (12-392); and for higher PCBs (HPCB), 30 (6-142) and 19 (4-108), respectively. The statistical associations among 42 measured clinical chemical and hematological parameters, five different measures of PCB exposure, and seven confounding variables observed in the two examinations were determined by three regression procedures. Similar regressions were performed with DDE, which was present at background levels. The principal statistical findings were a depression in serum bilirubin and elevations in serum GGTP and lymphocyte levels at the time of the first examination, and only an elevation in monocytes at the second. Appraisal of the results suggested an induction of microsomal enzymes which appeared to be subsiding after the cessation of direct exposure to PCBs. The statistical association between serum levels of PCBs and lipids reported by others was confirmed, but shown to be explained by the partitioning behavior of PCB in the body, rather than to changes in liver function. No evidence for health impairment related to PCBs was found, despite the high serum levels of PCBs in the study population.

Adipose Tissue↗
PubMed1985

[Congenital adrenal hyperplasia (21-OH) in France. Population genetics].

Incidence of congenital adrenal hyperplasia due to 21 hydroxylase deficiency was studied in France. Five hundred and twenty six patients born during the period 1963-1979 were found. Assuming complete ascertainment in females, the incidence of the disease is 0.43 X 10(-4) or 1: 23,044. The frequency of the carriers is 0.013 (1/76). The birth places of patients show an unequal geographic distribution. The mean inbreeding coefficient is 270 X 10(-5), a figure higher than the mean coefficient of France. The frequency of marriages between first cousins is slightly raised, 0.3%.

Adrenal Hyperplasia, Congenital↗
PubMed1984

Cluster of acute infantile spinal muscular atrophy (Werdnig-Hoffmann disease) in a limited area of Reunion Island.

A retrospective study of Werdnig-Hoffmann disease (spinal muscular atrophy type I) was undertaken on Reunion Island. Nineteen WH cases born between 1969 and 1980 were recorded belonging to thirteen sibships of the European population of the island. Genealogical analysis, going back to the XVIIth century (1642), showed a relationship among the 13 families, which were derived from a common ancestral pair. A founder effect is the most probable explanation for the concentration of Werdnig-Hoffmann disease in the area.

Adolescent↗
PubMed1984

An epidemiological and genetic study of facial clefting in France. II Segregation analysis.

Familial transmission of cleft lip with or without cleft palate (CL(P] and isolated cleft palate (CP) was studied in two French samples of 458 CL(P) and 156 CP nuclear families, using the recently implemented unified model. In neither case could discrimination be achieved between polygenic inheritance and monogenic inheritance with a high proportion of sporadic cases. In this type of disorder with a complex genetic basis the information furnished by such an approach, which only considers the affected status, is discussed. Future investigations on the joint familial transmission of the disease and different marker systems may help to identify the genes involved in these developmental anomalies.

Cleft Lip↗
PubMed1983

Familial congenital heart disease: how are the various types related?

The distribution of congenital heart lesions was studied in 238 families with at least 2 affected members. A statistical analysis was performed. Concordant lesions were found in 48% of the affected first degree relatives and in 28% of the affected second and third degree relatives. The concordance rate is highly significant for all lesions studied in the first degree relatives, with the exception of ventricular septal defect (VSD). Among the discordant pairs of lesions, some occur significantly more often than expected (tetralogy of Fallot associated with VSD, pulmonary stenosis, and transposition of the great arteries); others, such as the association between VSD and pulmonary stenosis, are significantly less common than would be expected on a random hypothesis. An explanation is proposed suggesting that malformations anatomically dissimilar but resulting from the same heart segment disorder may have some common genes, and that interaction between genes may be responsible for "antagonism" between 2 defects. The embryologic segmental approach to congenital heart disease is reinforced by this genetic study.

Female↗
PubMed1983

Reexamination of paternal age effect in Down's syndrome.

The recent discovery that the extra chromosome in about 30% of cases of 47, trisomy 21 is of paternal origin has revived interest in the possibility of paternal age as a risk factor for a Down syndrome birth, independent of maternal age. Parental age distribution for 611 Down's syndrome 47, +21 cases was studied. The mean paternal age was 0.16 year greater than in the entire population of live births after controlling for maternal age. There was no evidence for a significant paternal age effect at the 0.05 level. For 242 of these Down's syndrome cases, control subjects were selected by rigidly matching in a systematic manner. Paternal age was the variable studied, with maternal age and time and place of birth controlled. There was no statistically significant association between paternal age and Down's syndrome. After adjustment for maternal age, these two studies were not consistent with an increase of paternal age in Down's syndrome.

Adolescent↗
PubMed1983

[Rubella and congenital cataracts].

Between April 3, 1977 and June 6, 1980, 97 children with congenital cataracts and 97 evenly matched control children were examined in order to clarify the biological criteria of congenital rubella and to estimate its importance in the etiology of congenital cataracts. Although the age limit had been fixed at 60 months, the 1978 rubella outbreak accelerated the immunization in young children and resulted in difficulties in interpreting some results. All children presenting with congenital cataracts associated with clinical symptoms of rubella embryopathy displayed anti-rubella antibodies including anti-rubella IgM up to the 13th month: they represent 16% of cases with congenital cataracts in this series. The rubella etiology could not be proven in children with clinically isolated congenital cataracts.

Antibodies, Viral↗