摘要:

Variable number of tandem repeat (VNTR) DNA polymorphisms were studied in a random sample of 100 Italians. The following systems were used: YNH24/MspI, CMM101/Msp1, MLJ14/RsaI, EFD64.2/RsaI, EFD64.2/HinfI, JCZ3.1/HinfI and AW101/EcoRI. For each system, the allele size, number and frequency were determined. The number of alleles, for the different VNTRs, varied from 21 to 44, and the heterozygosity from 70 to 90%. All the VNTRs showed a modal distribution of fragment size and overrepresentation of the lower-molecular-weight DNA fragments. All of them exhibited greater variability than that reported for the North American population. These data will be useful for individual identification purposes and for calculating the probability of random inheritance of a particular allele in the Italian population. The results are discussed in relation with the possible mechanism of generation of new-length alleles.

ISSN:0001-5652    

DOI:10.1159/000153907

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

In order to investigate the modes of inheritance of serum immunoglobulin E (IgE) levels and atopic disease, serum IgE levels and data on allergic disease were obtained from 42 families ascertained through asthmatic children visiting an allergy clinic. Although the mean IgE levels were elevated (mean 637 U/ml), the prevalence of atopic disease in this population was surprisingly low. When the data were analyzed using complex segregation analysis, no major locus could be detected. Moreover, the polygenic heritability was unexpectedly small even though the correlation between serum IgE levels and the liability to atopic disease was around 0.4. Given this unusual set of findings, it is postulated that parasitic infections in this population have (in accordance with well-established results of parasitic disease) caused both elevated levels of serum IgE and a decreased prevalence of allergic disease with the possible masking of the various genetic components of serum IgE levels and atopic disease.

ISSN:0001-5652    

DOI:10.1159/000153908

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Locus-specific minisatellite probes detect multiple alleles with heterozygosities of greater than 90% when hybridised to Hinfl and Alul restriction digests of human DNA. We have hybridised 4 of these probes to a panel of DNAs digested with 6 of the restriction enzymes which commonly reveal diallelic polymorphisms in the human genome. All 6 enzymes detected multiple resolvable alleles with at least 1 of the 4 minisatellite probes tested, thus providing a rapid and efficient means to check family relationships and paternity on filters already being used for linkage analysis.

ISSN:0001-5652    

DOI:10.1159/000153909

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

A 1-year-old boy with trisomy 18 (pter→q12) following a paternal balanced translocation revealed microcephaly, a pattern of minor dysmorphic features including upslanting narrow palpebral fissures, receding forehead, large nose and receding mandible, cryptorchidism, flexion contractures of fingers, a cardiac malformation and moderate mental retardation. While pure trisomy 18p generally goes along with a near-normal phenotype, additional trisomy of only a short segment of the proximal long arm 18 has a distinct negative influence on the phenotype, as seen in our proban

ISSN:0001-5652    

DOI:10.1159/000153910

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

The frequency of α-thalassemias in a general population sample from northeastern Thailand and in an Austroasiatic group with high frequencies of hemoglobin E and β-thalassemia, the So, was estimated using DNA techniques. Among 64 healthy adult subjects from the Khonkaen and Ubol areas, the following haplotype frequencies were determined: αα, 0.742; -α3.7 (subtype I), 0.148; -α4.2, 0.016; -αdel, 0.008; Constant springy 0.055. __sea, 0.023 and ααα (triplicated α-globin gene), 0.008. In the So group, the combined frequency of α-thalassemia chromosome

ISSN:0001-5652    

DOI:10.1159/000153911

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Salivary proline-rich protein (PRP) polymorphism, PRH1, PRH2, Ps, Pm (PmF), PmS and Gl, were investigated in three ethnic groups in Singapore: Chinese, Malays and Indians. The phenotype and gene frequencies were presented and comparison with other ethnic groups was made. The As protein, which was recently found in Japanese but not in Caucasians as a new allelic product of the PRH1 locus, was also observed in Chinese and Malays but not in Indians. Another allelic product (Ps4) of Ps protein polymorphism was found in Malays but not in Chinese and Indians. The results indicate the usefulness of salivary PRP polymorphism as markers in population genetic studies.

ISSN:0001-5652    

DOI:10.1159/000153912

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Twenty unrelated people with thermolabile β-hexosaminidase (Hex) B were identified in random samples Of 41,561 adult Israeli Jews whose sera were screened for Hex A levels. Eighteen of them originated from contiguous Middle Eastern countries (n = 1,337) and only 2 were Ashkenazi Jews (n = 38,388). None was found among the screened Moroccan Jews (n = 1,524). The commonly used screening test for detection of Tay-Sachs disease (TSD) carriers is the serum Hex heat inactivation method (HIM), which is based on the assumption that Hex A is the only thermolabile component of Hex; However, in the presence of thermolabile Hex B, HIM could lead to false-negative results. Since TSD is very rare among Mideastern Jews while thermolabile Hex B is very rare among Ashkenazi and Moroccan Jews, it is concluded that at present there is almost no risk of such false-negative results. In order to further reduce this risk it is recommended that screening of people of Mideastern or mixed ancestry be done with HIM in leukocytes rather than in serum or with the specific substrate for Hex A in serum

ISSN:0001-5652    

DOI:10.1159/000153913

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

A genetic linkage study of fifteen families (n = 166) ascertained through probands diagnosed for Tourette syndrome was carried out for the D2-dopamine receptor and flanking loci on chromosome 11q22-q23. Tight linkage was excluded for all probes and regions of exclusion up to ± 20% recombination were obtained. Overlapping regions of exclusion based upon primary map data permit exclusion of the entire region of the DRD2 locus in Tourette syndrome

ISSN:0001-5652    

DOI:10.1159/000153914

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

Linkage between chromosome 5 markers and schizophrenia has been proposed for a small number of Icelandic and English families. Three subsequent reports have failed to replicate this report. To increase the number of tested kindreds, we collected seven North American families with schizophrenia and genotyped them at 4 loci that span the region 5p13–5q11–14, including the two markers used in the single positive linkage report. The data were analyzed with models of affection status similar to those utilized in the positive report. We observed no evidence of linkage between these markers and psychiatric disorders, regardless of the definition of affection status. Additionally, we can exclude most of the region for linkage with schizophrenia in these families. This and other negative reports of linkage between schizophrenia and chromosome 5 markers suggest that genetic defects in this region are rarely, if ever, etiologically related to schizophre

ISSN:0001-5652    

DOI:10.1159/000153915

出版商:S. Karger AG    

年代:1990

数据来源: Karger

摘要:

α1-Antitrypsin (PI) types were studied in patients with toxoplasmosis (n = 84) and controls (n = 143) using isoelectric focusing. The patients showed a lower frequency of rare types (p < 0.025) and a higher frequency of individuals with increased PI levels (p < 0.005) compared to controls

ISSN:0001-5652    

DOI:10.1159/000153916

出版商:S. Karger AG    

年代:1990

数据来源: Karger