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Hemophilia A is a clotting disease caused by defects in the F8 gene. A lot of them are described and most are unique or have polyphyletic origin. We here study the origin of a pathogenic variant found in a few patients. We sequenced F8 gene for seven hemophilia A patients from the Ural region, Sverdlovskaya oblast, Russia. We constructed haplotypes for them and for 21 hemophilia A patients with other defects from the same area as a control group using four previously described X-chromosome loci associated with F8 gene. We identified a new missense variant p.(His634Arg) in seven apparently unrelated patients with mild hemophilia A from Sverdlovskaya oblast. The haplotype analysis showed that all patients share the same haplotype, absent in the other patients, suggesting a founder effect. The most recent common ancestor for the p.(His634Arg) patients is estimated to exist around the end of XVII century; however, the 95% confidence interval spans from XII to early XX century. The Ural region did not suffer from the recent bottlenecks or isolation. Therefore, the founder effect could be a natural consequence of population structuring in a relatively stable population. We identified a founder effect mutation in hemophilia A, which is a quite rare event for this disease.

The study of activating mutations (NRAS,KRAS,FLT3,JAK2,CRLF2genes) of RAS/RAF/MEK/ERK and JAK/STAT signaling pathways in B-cell acute lymphoblastic leukemia (B-ALL) in adult patients which are included in Russian multicenter clinical trials.Within the multicenter study there were 119 adult patients included withde novoB-ALL. The study was considered as prospective and retrospective. The group withBCR-ABL1-negative B-ALL consisted of up to 93 patients (45 male and 48 female, at the age of 17 to 59, the median age 31), they were treated according to the protocols ALL-2009, ALL-2016. The median follow-up lasted for 19 months (1119). The group withBCR-ABL1-positive B-ALL with up to 26 patients (10 male and 16 female, at the age of 23 to 78, the median age 34 years) was included in the study as well. The treatment was carried out according to the protocols ALL-2009 and ALL-2012 in combination with tyrosine kinase inhibitors. The median follow-up lasted for 23 months (4120). The molecular analysis of activating mutations inNRAS,KRASgenes (RAS/RAF/MEK/ERK signaling pathway) andJAK2,CRLF2genes (JAK/STAT signaling cascade) was performed via Sanger sequencing. The internal tandem duplications (ITDs) inFLT3gene were studied by fragment analysis. The evaluation of CRLF2 expression was fulfilled via flow cytometry.Activating mutations inNRAS,KRAS,FLT3genes were found in 22 (23.6%) patients withBCR-ABL1-negative B-ALL. In total, 23 mutations were revealed in theNRAS(n=9),KRAS(n=12), andFLT3(n=2) genes, according to statistics that was significantly more frequent than withBCR-ABL1-positive B-ALL, these genes mutations were not identified in patients (p=0.007). The frequency of mutations detection inKRASandNRASgenes in patients withBCR-ABL1-negative B-ALL was comparable as 12.9% (12 of 93) to 9.7% (9 of 93), respectively (p=0.488). One patient was simultaneously revealed 2 mutations in theKRASgene (in codons 13 and 61).FLT3-ITD mutations were detected in 3.5% (2 of 57) cases ofBCR-ABL1-negative B-ALL. In patients withBCR-ABL1-positive B-ALLFLT3-ITD mutations were not assessed. Violations in the JAK/STAT signaling cascade were detected in 4 (4.3%) patients withBCR-ABL1-negative B-ALL. They were represented by the missense mutations ofJAK2gene (n=3) and the overexpression of CRLF2 (n=2); in one patient were detected the overexpression of CRLF2 and a mutation inJAK2gene simultaneously. No mutations were found inCRLF2gene. In patients withBCR-ABL1-positive B-ALL noJAK2mutations were detected. As long as analyzing demographic and clinical laboratory parameters between groups of patients with and without mutations, there were no statistically significant differences obtained. In the analyzed groups of patients, long-term therapy results did not differentiate according to the mutations presence inNRAS,KRAS,FLT3,JAK2genes. Also, substantive differences were not shown in the rate of the negative status achievement of the minimum residual disease between patients with and without activating mutations in the control points of the protocol (on the 70th, 133rd and 190th days).NRAS,KRAS,FLT3,JAK2activating mutations do not affect the long-term results of the therapy and the rate of the negative status achievement of the minimum residual disease in patients withBCR-ABL1-negative B-ALL treated by the Russian multicenter clinical trials.Цель.Изучение активирующих мутаций генов (NRAS,KRAS,FLT3,JAK2,CRLF2) сигнальных каскадов RAS/RAF/MEK/ERK и JAK/STAT при В-клеточном остром лимфобластном лейкозе (В-ОЛЛ) у взрослых больных, включенных в российские многоцентровые исследования. Материалы и методы.В многоцентровое исследование включены 119 взрослых пациентов с впервые установленным В-ОЛЛ. Исследование носило проспективный и ретроспективный характер. Группа сBCR-ABL1-негативным В-ОЛЛ составила 93 больных (48 женщин и 45 мужчин от 17 до 59 лет, медиана возраста 31 год), им проводили терапию по протоколам ОЛЛ-2009, ОЛЛ-2016. Медиана наблюдения составила 19 мес (1119). В группу сBCR-ABL1-позитивным В-ОЛЛ включены 26 пациентов (16 женщин и 10 мужчин от 23 до 78 лет, медиана возраста 34 года). Лечение проводили по протоколам ОЛЛ-2009 и ОЛЛ-2012 в сочетании с ингибиторами тирозинкиназ. Медиана наблюдения составила 23 мес (4120). Молекулярный анализ активирующих мутаций для геновNRAS,KRAS(сигнальный путь RAS/RAF/MEK/ERK) и геновJAK2,CRLF2(сигнальный путь JAK/STAT) проводился методом секвенирования по Сэнгеру. Внутренние тандемные повторы (ITD) генаFLT3 рецепторной внутриклеточной тирозинкиназы, приводящие к запуску целого каскада реакций, относящихся к различным сигнальным путям, включая RAS/RAF/MEK/ERK и JAK/STAT, исследованы методом фрагментного анализа. Экспрессию белка CRLF2 оценивали методом проточной цитофлуориметрии. Результаты.Активирующие мутации в генахNRAS,KRAS,FLT3обнаружены у 22 (23,6%) больныхBCR-ABL1-негативным В-ОЛЛ. В общей сложности выявлено 23 мутации в генахNRAS(n=9),KRAS(n=12),FLT3(n=2), что статистически значимо чаще, чем приBCR-ABL1-позитивном В-ОЛЛ, где мутации этих генов не выявлены ни у одного больного (р=0,007). Частота обнаружения мутаций в генахKRASиNRASу больныхBCR-ABL1-негативным В-ОЛЛ сопоставима 12,9% (12 из 93) и 9,7% (9 из 93) соответственно (р=0,488). У одного больного выявлено одновременно 2 мутации в генеKRAS(в кодонах 13 и 61). МутациюFLT3-ITD детектировали в 3,5% (2 из 57) случаевBCR-ABL1-негативных В-ОЛЛ. У больныхBCR-ABL1-позитивным В-ОЛЛ мутациюFLT3-ITD не оценивали. Нарушения в сигнальном каскаде JAK/STAT обнаружены у 4 (4,3%) больныхBCR-ABL1-негативным В-ОЛЛ. Они представлены миссенс-мутациями генаJAK2(n=3) и гиперэкспрессией CRLF2 (n=2), у одного больного обнаружены одновременно гиперэкспрессия CRLF2 и мутация в генеJAK2. В генеCRLF2мутации не выявлены. У больныхBCR-ABL1-позитивным В-ОЛЛ мутаций генаJAK2не выявлено. При анализе демографических и клинико-лабораторных показателей между группами больных с мутациями и без таковых статистически значимых различий не получено. В анализируемых группах больных долгосрочные результаты терапии в зависимости от наличия мутаций в генахNRAS,KRAS,FLT3,JAK2не различались. Также не показано значимых отличий в скорости достижения негативного статуса минимальной остаточной болезни между пациентами с активирующими мутациями и без в контрольные сроки протокола (на 70, 133 и 190-й день). Заключение.Активирующие мутации геновNRAS,KRAS,FLT3,JAK2не влияют на долгосрочные результаты терапии и скорость достижения негативного статуса минимальной остаточной болезни у больныхBCR-ABL1-негативным В-ОЛЛ при применении протоколов российского многоцентрового исследования.

The article provides review of possible mechanisms of inhibitor coagulopathies, in particular of acquired hemophilia A. This pathology is an extremely rare disease occurring in 1-2 cases in 1 million per year. In the present study we provide data for two clinical cases of hemophilia A in women. These cases had different development mechanisms, although both women have a newly discovered missense mutation His2026Arg in the VIII factor gene. The matter of main interest is the description of the disease development in the patient with an acquired idiopathic hemophilia A with a possible disease occurrence due to an asymmetric X-chromosome inactivation (lyonization). In this particular case lyonization led to the late manifestation of the hemophilia A carrier’s state and development of severe form of the inhibitor-associated acquired hemophilia A. We also discuss therapeutic approaches to these forms of the disease, considering there are no concise protocols for case management due to an extreme rarity of the pathology. Acquainting the clinical personnel working it the different areas of medicine with suchlike inhibitor coagulopathies has a major practical importance.

Clonal composition of human multipotent mesenchymal stromal cells (MMSCs) labeled with lentiviral vectors carrying genetic barcodes was studied. MMSCs were transduced with a cloned library of self-inactivating lentiviral vectors carrying 667 unique barcodes. At each cell culture passage, 120 cells were plated one cell per well in 96-well plates. The efficiency of cloning and labeling of the clonogenic cells was determined. DNA was extracted from the cell-derived colonies, and the barcodes were identified by Sanger sequencing. Also, DNA was extracted from the total MMSC population at each passage to analyze the diversity and representation of barcodes by deep sequencing using the Illumina platform. It was shown that the portion of MMSCs labeled with the lentiviral vectors remained stable in the passaged cells. Because of the high multiplicity of infection, the labeling procedure could decrease the proliferative potential of MMSCs. Identification of barcodes in individual cell clones confirmed the polyclonal character of the MMSC population. Clonal composition of MMSCs changed significantly with the passages due to the depletion of proliferative potential of most cells. Large clones were found at the first passage; at later passages, many small clones with a limited proliferative potential were detected in the population. The results of deep sequencing confirmed changes in the clonal composition of MMSCs. The polyclonal MMSC population contained only a small number of cells with a high proliferative potential, some of which could be stem cells. MMSCs with a high proliferative potential were detected more often in the earliest passages. In this regard, we would recommend to use MMSCs of early passages for regenerative medicine applications based on cell proliferation.

Comprehensive analysis of molecular pathology requires a collection of reference samples representing normal tissues from healthy donors. For the available limited collections of normal tissues from postmortal donors, there is a problem of data incompatibility, as different datasets generated using different experimental platforms often cannot be merged in a single panel. Here, we constructed and deposited the gene expression database of normal human tissues based on uniformly screened original sequencing data. In total, 142 solid tissue samples representing 20 organs were taken from post-mortal human healthy donors of different age killed in road accidents no later than 36 hours after death. Blood samples were taken from 17 healthy volunteers. We then compared them with the 758 transcriptomic profiles taken from the other databases. We found that overall 463 biosamples showed tissue-specific rather than platform- or database-specific clustering and could be aggregated in a single database termed Oncobox Atlas of Normal Tissue Expression (ANTE). Our data will be useful to all those working with the analysis of human gene expression., Design Type(s)gene expression analysis objective • data integration objective • organism part comparison design • transcription profiling designMeasurement Type(s)transcription profiling assayTechnology Type(s)RNA sequencingFactor Type(s)sex • age • organism subdivisionSample Characteristic(s)Homo sapiens • kidney • Kidney • Colon • Liver • brain • Lung • endometrium • Ovary • prostate gland • Esophagus • Stomach • Mammary gland • Thyroid gland • Pancreas • Tonsil • skeletal muscle tissue • small intestine • Adrenal gland • urinary bladder • skin of body • uterus • uterine cervix • Small intestine • tonsil • blood • bone marrow • esophagus • liver Machine-accessible metadata file describing the reported data (ISA-Tab format)

Acute intermittent porphyria (AIP) is the most common and severe form of porphyrias. This is a dominant inherited disorder with low penetrance, caused by mutations in gene coding hydroxymethylbilane synthase (HMBS). We present the results of our long-term genetic study of AIP patients and their relatives (N = 153 and 302, respectively). We detected 88 HMBS gene mutations, 24 of which never described before. To identify additional factors conditioning AIP manifestation, we carried out whole exome sequencing on the group of AIP patients (N = 6). Mutation spectra of different patients virtually did not overlap. In 5 out of 6 patients, we found defects in genes regulating nervous system (UNC13A, ALG8, FBXO38, AGRN, DOK7, SCN4A). As usually acute AIP attacks have various neurological symptoms, we proposed a hypothesis of possible contribution of mutations in such genes in AIP manifestation.

Hemophilia B is a hereditary X-linked coagulation disorder. This pathology is caused by various defects in the factor IX gene, which is, being about 34 kb long and consisting of eight exons, localized in the Xq27 locus of the. X-chromosome long arm. Mutations were revealed in 56 unrelated patients with hemophilia B in this study by using direct sequencing of factor IX gene functionally important fragments. Forty-six mutations were found with prevailing missense mutations (n = 30). The rest of the mutations were nonsense (n = 4) and splicing (n = 4) mutations, large deletions (n = 3), microdeletions (n = 2), microinsertions (n = 2), and promoter mutations (n = 1). Eleven of 46 mutations were previously unknown for human populations.

We developed a method for gene transfer into mesenchymal stromal cells. Lentivirus vector containing green fluorescent protein gene for labeling stromal and hemopoietic precursor cells was obtained using two plasmid sets from different sources. The vector was injected into the femur of mice in vivo and added into culture medium for in vitro infection of the stromal sublayer of long-term bone marrow culture. From 25 to 80% hemopoietic stem cells forming colonies in the spleen were infected with lentivirus vector in vivo and in vitro. Fibroblast colony-forming cells from the femoral bones of mice injected with the lentivirus vector carried no marker gene. The marker gene was detected in differentiated descendants from mesenchymal stem cells (bone cavity cells from the focus of ectopic hemopoiesis formed after implantation of the femoral bone marrow cylinder infected with lentivirus vector under the renal capsule of syngeneic recipient). In in vitro experiments, the marker gene was detected in sublayers of long-term bone marrow cultures infected after preliminary 28-week culturing, when hemopoiesis was completely exhausted. The efficiency of infection of stromal precursor cells depended on the source of lentivirus. The possibility of transfering the target gene into hemopoietic precursor cells in vivo is demonstrated. Stromal precursor cells can incorporate the provirus in vivo and in vitro, but conditions and infection system for effective infection should be thoroughly selected.

to estimate the spread of weak D antigen types of the Rhesus system in the citizens of the Russian Federation and a possibility of serologically identifying these types.The red blood cells and DNA of people with weakened expression of D antigen were investigated using erythrocyte agglutination reaction in salt medium (2 methods); agglutination reaction in the gel columns containing IgM + IgG anti-D antibodies, indirect antiglobulin test with IgG anti-D antibodies (2 methods); polymerase chain reaction to establish the type of weak D.A rhesus phenotype was determined in 5100 people in 2014-2015. The weakened agglutinable properties of red blood cells were detected in 102 (2%) examinees. 63 examinees underwent genotyping to identify the variants of the weak D antigen, which identified 6 weak D types. There were the most common weak D types 3 (n=31 (49.2%)) and weak D type 1 (n=18 (28.6%)), including weak D type 1.1 in one (1.6%) case. The other 4 weak D antigen types were as follows: weak D type 2 (14.3% (n=9)), weak D type 15 (4.8% (n=3)), weak D type 4.2 (DAR) (1.6% (n=1)) and weak D type 6 (1.6% (n=1)). The antiglobulin test in the gel column containing antiglobulin serum was the most sensitive serological assay to identify the weak D antigen. Only a molecular test could establish weak D type 15 in 2 samples of red blood cells with Ccdee and ccdEe phenotypes.The weak D antigen could be serologically identified in 96.8% of cases. When testing for weak D, particular attention should be given to people with the D-negative phenotype who had the C or E antigens. Our investigations conducted for the first time in Russia will be able to improve the immunological safety of red blood cell-containing medium transfusions for patients.Цель исследования. Оценка распространенности типов слабого антигена D (weak D) системы резус у россиян и возможности выявления этих типов серологическими методами. Материалы и методы. Исследовали эритроциты и ДНК людей с ослабленной экспрессией антигена D с помощью реакции агглютинации эритроцитов в солевой среде (2 метода); реакции агглютинации в гелевых колонках с IgM+IgG анти-D-антителами, непрямого антиглобулинового теста с IgG анти-D-антителами (2 метода); полимеразной цепной реакции для установления типа weak D. Результаты. В 2014-2015 гг. резус-фенотип определен у 5100 человек. Ослабление агглютинабельных свойств эритроцитов выявлено у 102 (2%) обследованных. Генотипирование для идентификации вариантов антигена weak D проведено у 63 обследованных, выявлено 6 типов weak D. Наиболее частыми оказались типы weak D type 3 (n=31; или 49,2%) и weak D type 1 (n=18; или 28,6%), в том числе в одном случае weak D type 1.1 (1,6%). Остальные 4 типа антигена weak D имели следующие частоты: weak D type 2 - 14,3% (n=9), weak D type 15 - 4,8% (n=3), weak D type 4.2 (DAR) (n=1) и weak D type 6 (n=1) - по 1,6% каждый. Наиболее чувствительным серологическим методом идентификации антигена weak D был антиглобулиновый тест в гелевых колонках, содержащих антиглобулиновую сыворотку. В 2 образцах эритроцитов с фенотипами Ccdee и ccdEe наличие weak D type 15 установлено только молекулярным методом. Заключение. Серологическими методами слабый антиген D выявлен в 96,8% случаев. Особое внимание при проверке на наличие weak D следует уделять людям с D-отрицательным фенотипом, имеющим антигены С или Е. Наши исследования, проведенные впервые в России, позволят улучшить иммунологическое обеспечение безопасности трансфузий пациентам сред, содержащих эритроциты.

In search of new efficient markers for genetic diagnostics of hemophilia A, two tri-nucleotide microsatellite repeats (STR) at chromosome X loci, which flank coagulation factor VIII gene (F8), namely STR HA472--CTT-repeat, which is localized adjacent to the GAB3 gene 163 bp apart from the 3' end of the F8 gene and STR HA544--repeat (CTT)x(ATT)y located at a distance of 375 bp from the 5' end of the F8 gene were discovered. Detailed analysis using PCR and sequencing has shown that STR HA472 contains two long variable CTT-blocks separated by small spacer CCTCCC. The location of recognition site of restriction endonuclease Mnl1 (CCTC) in the spacer permits to test differentially the polymorphic blocks and thus to increase the analysis informativity. STR HA544 is also represented by two polymorphic blocks (CTT and ATT), for separate amplification of which highly informative PCR amplification assays were elaborated. The study has been done using DNA samples of 212 individuals (125 women) from 48 families with hemophilia A carriers. Our results point to Mendelian inheritance of the markers studied, a high number of allelic variants and high heterozygosity, which was 90% and 100% for HA544 and HA472, respectively. This permitted us to use these data for practical gene diagnostics of the carriers and prenatal diagnostics of hemophilia A. In addition to high informativity STR HA472 and HA544 are highly important for diagnostics as they are located at a shorter distance than other known extragenic polymorphisms of the F8 gene. In contrast to dinucleotide repeats, trinucleotide repeats are readily tested, not requiring high-resolution electrophoretic systems. In addition, they are located on the opposite sites of the F8 gene. This permits to control homologous recombination events in the locus and thus to prevent diagnostic mistakes.

Frequencies of the CIT SNP alleles at position 2403 of the human coagulation factor VIII gene intron 1, containing the AluI restriction endonuclease recognition site, were examined. Genomic DNA samples for the analysis were obtained from the consulted women and their relatives from the families with hemophilia A. A total of 221 unrelated X chromosomes were studied. The two allelic variants were found with similar frequencies of T(Alu+), 0.53 and C(Alu-), 0.47. The heterozygosity index evaluated as equal to 0.50 was correlated with the experimental heterozygote number. The absence of a tight linkage between the AluI SNP and the widely used in the hemophilia A gene diagnostics HindIII polymorphism (CIT SNP at position 103 of intron 19) was demonstrated. Summarized informativity of these two markers for obligate carriers and for those detected in this study constituted 68% (32 out of 47). At the same time using one of the markers, only 40% (HindIII) and 51% (AluI) of the consulted women were informative. The new marker was used in 13 prenatal DNA diagnostics of hemophilia A. A new deletion polymorphism (del TGA, position 2281-2283 of intron 1) was described in close proximity of the AluI SNP with the frequency of about 0.05. among the five other SNP of the factor VIII gene examined (Bme 18I, intron 1; HpaII, intron 13; MnlI, exon 14; Bst4CI, exon 25; and MseI, exon 26) no effective diagnostic markers were found. Only the MnlI polymorphism could be recommended for limited usage.

To investigate effectiveness of allogenic transplantation of the bone marrow (TBM) in the treatment of hemoblastosis patients from a high risk group, the course of donor bone marrow retention, tolerance and antitumor activity of this therapy.11 patients received TBM in low-intensity regimen in Hematological Research Center in 1999-2001. All the patients were from a high risk group. Conditioning was based on the combination of fludarabin with busulfan. The transplanted precursor cells were taken from the bone marrow and/or peripheral donor blood. The retention was controlled by differential agglutination of erythrocytes and amplification of hypervariable sites of DNA. Minimal residual disease was controlled by standard cytogenetical tests, fluorescent in situ hybridization or reverse-transcriptase polymerase chain reaction.All the patients tolerated pretransplantation conditioning well. By chimerism, signs of retention of donor bone marrow on day +30 after TBM were observed in 9 patients of 11. Acute graft versus host reaction developed in 5 patients. This reaction was treated conventionally with methylprednisone and cyclosporin A, in 4 cases with a good effect. A complete remission persists in 5 patients. Mean follow-up lasted for 241 days.Thus, transplantation was successful in 50% patients with an unfavourable prognosis who are still in a complete remission. This suggests efficacy of the above method of treatment.

To establish the type of hemopoiesis in 15 patients with hemoblastosis subjected to allogenic bone marrow transplantation, the amplification of four hypervariable human genome loci containing tandem repeats with varying copy numbers (loci ApoB, DX, S52, VWF, and YNZ22) were studied by means of polymerase chain reaction. The sensitivity determined by amplification of DNA mixture in dilutions was 1-2%. Based on the data obtained, various types of hemopoiesis recovery after bone marrow transplantation were determined; in most cases, a complete donor chimerism was revealed; in some patients, mixed chimerism; and in one case, a host type of hemopoiesis was found. An association between hemopoiesis type and further development of the disease was observed.

A T-to-C substitution, replacing a hydrophobic isoleucine residue with a hydrophilic threonine residue in position 100 of a mature protein molecule, was found at codon 117 of the GM-CSF gene. The mutation frequencies were estimated in 51 DNA samples from healthy adult donors and also in 20 samples from patients with different neoplastic myeloid disorders. Almost equal substitution frequencies in patients and normal individuals were observed, suggesting that the defect was not associated with leukemia. Additionally the GM-CSF gene intron 1 sequence was refined.

The polymorphism of Alu-repeats, which are located in the introns of the human factor IX gene (copies 1-3), was studied. To identify polymorphic variants, direct sequencing of PCR products that contained appropriate repeats was used. In each case, 20 unrelated X chromosomes were studied. A polymorphic Dra I site was found near the 3'-end of Alu copy 3 within the region of the polyA tract. A PCR-based testing system with internal control of restriction hydrolysis was suggested. Testing 81 unrelated X chromosomes revealed that the frequency of the polymorphic Dra I site is 0.23. Taq I polymorphism, which was revealed in Alu copy 4 of factor IX gene in our previous work, was found to be closely linked to Dra I polymorphism. Studies in linkage between different types of polymorphisms of the factor IX gene revealed the presence of a rare polymorphism in intron A that was located within the same minisatellite region as the known polymorphic insertion 50bp/Dde I. However, the size of the insertion in our case was 26 bp. Only one polymorphic variant was found among over 150 unrelated X chromosomes derived from humans from Moscow and its vicinity.

The frequency of different polymorphic variants of the multiallelic locus DXS52 (St14) of the human X-chromosome, adjacent to the factor VIII gene, was evaluated by means of PCR for the heterogeneous population of Moscow and Moscow oblast'. It was shown that the heterozygosity index of this polymorphism in the studied population is much lower (0.71) than in Western Europe (0.80-0.85), which can apparently be explained by a higher frequency of the prevailing allele 1690 (0.52 compared to 0.36). Five new St14 alleles were detected during this study. The total informativity of the polymorphic markers St14 and HindIII (intron 19 of the factor VIII gene), which are most commonly used for hemophilia A detection, was evaluated. Among 83 investigated women, only 57 (69%) were heterozygous for at least one of the markers used, which is also much lower than in Western-European populations (90-95%).

A new Taq I polymorphism in Alu repeat 4 of the human factor IX gene is reported. This polymorphism is associated with a C-T transition at the 72-bp position of the Alu repeat consensus sequence. A simple PCR system for testing of this structural anomaly, with internal control of restriction hydrolysis, was developed. The frequency of the new polymorphic site and its linkage with other polymorphisms of the factor IX gene were also evaluated. The new polymorphism was used for establishing hemophilia B carriers.

The DNA probes--pA6-CSF-1 and pA2-CSF-1 for the alternative splicing region of the 6 exon human CSF-1 gene were prepared using PCR and subsequent subcloning in pUC19 plasmid at the XmaI/BamHI sites. Due to the insert sequencing and blotting of human leukocytes DNA, the DNA probes obtained can be useful for screening of mutations in the human CSF-1 gene.

Prenatal DNA-diagnosis of beta-thalassemia in a family from Azerbaijan revealed two mutations new for this region--G-A transition at codon 15 and G-C transversion at position 5 of the intron 1. Prenatal diagnosis was carried out by direct sequencing of in vitro amplified (PCR) beta-globin gene fragments with a modified Sanger technique using thermostable DNA polymerase. The absence of parents mutations in the fetal DNA allowed us to conclude that the fetus is normal. The diagnosis was proved at hematological testing of the baby borne.

New systems are proposed for the PCR analysis of HindIII polymorphic sites in the gamma A and gamma G globin genes and of TaqI polymorphic site in the human factor IX gene of blood population. DNA fragments amplified according to the systems described contain constant restriction site of the appropriate endonuclease, in addition to the polymorphic one, which significantly improves the reliability of the RELP analysis. The systems proposed are highly specific and may be used for DNA diagnosis of beta-thalassemia and haemophilia B.

Thirty tajiks, whose relatives had beta-thalassemia traits (revealed in previous investigations by determination of the HbA-2 and HbF levels) were selected to screen beta-thalassemia mutations. DNA samples from each individual were subjected to the PCR (polymerase chain reaction) to amplify the 635 bp beta-globin gene fragment. One additional band was detected in three samples after the amplified fragment underwent electrophoresis in 2% agarose gel and the EtBr was stained, and two additional ones were revealed by 6% PAAGE and staining of the EtBr. All additional bands migrated more slowly than appropriate 635 bp fragment. It is supposed that additional bands are heteroduplexes formed from the wild type chains and mutated chains carrying a deletion or insertion. The 4 bp deletion of the 41-42 (-tctt) was detected after the direct sequencing of the amplified fragments. This mutation is common among Chinese but it was not revealed in the Middle Asia populations. The mutation can be easily screened using the PCR and electrophoresis in 2% agarose gel or PAAG of the amplified beta-globin gene fragments.

Allele polymorphism has been evaluated using blot hybridization and a polymerase cascade of DNA synthesis in 40 families at high risk of hemophilia A (a total of 147 subjects) and in 15 families with Duchenne's myodystrophy, Heterozygous carriage of hemophilia A was identified or confirmed in 18 and ruled out in 4 close female relatives of probands. Prenatal tests for fetal hemophilia A were performed in 5 women from families with hemophilia A (in the 1st trimester in 2 and in the 2nd trimester in 3). Four diagnoses of hemophilia A were confirmed and 1 was ruled out. The DNA methods proved revealing in 34 of 40 families with hemophilia A and in 11 of 15 families with Duchenne's myodystrophy. Three of 9 probands were found to have a deletion of the proximal gene for Duchenne's myodystrophy in the DNA probe area of XY 1.1. Prospects of screening for heterozygous carriage and prenatal identification of hemophilia A and Duchenne's myodystrophy are discussed.

Representatives of 62 families from Moscow and Leningrad with haemophilia A observed in the pedigree were tested for HindIII polymorphism in the factor VIII gene. The proposed scheme of investigation was based on intron 19 of the FVIII gene amplification by the PCR technique followed by restriction analysis with the inner control of hydrolysis. 207 unrelated X-chromosomes were analysed, the frequency of the incidence of the polymorphic HindIII site in the given population found to be 0.29. The frequency of incidence of the HindIII heterozygotes calculated according to Hardy-Weinberg equation was 0.41. This value evidences for relatively high informativity of this polymorphism for carrier detection and prenatal diagnosis of haemophilia A. 23 families (37%) out of 62 examined in the study were informative for this criteria. The new scheme proved to be effective in testing HindIII polymorphism for haemophilia A carrier detection and prenatal diagnosis. The whole procedure takes one day, the radiolabelled probes are not used. The scheme described was inculcated in the All-Union Research Center for Haematology, Ministry of Health, USSR, Moscow, Research Institute for Obstetrics and Gynecology, Leningrad, Institute of Medical Genetics, Greifswald, DDR.

A method is described which uses the Hind III polymorphism in intron 19 of the factor VIII gene for genomic family analysis and prenatal diagnosis by the polymerase chain reaction. The primers derived from the exon 19 and 20 sequences allow amplification of the whole intron 19 resulting in a 730 bp fragment. Hind III restriction of this fragment provides fragments of 250 bp or 160 bp and 90 bp respectively, specific for the intragenic Hind III polymorphism. The constant 480 bp fragment can be used as an internal control to circumvent misdiagnosis due to incomplete or failure of restriction. Using this method a prenatal diagnosis of haemophilia A in the first trimester of pregnancy is demonstrated.

A new variant of the PCR test system is discussed which allows one to detect Bcl I and Hind III polymorphic sites of FVIII gene. It can be used for rapid and effective diagnosis of hemophilia A, especially, in combination with the blot-hybridization technique that detects other polymorphic variants of FVIII gene. The method proposed is highly accurate, reliable and simple. It allows one to analyze submicrogram quantities of DNA without using radiolabeled probes. The whole procedure takes several hours. The variant discussed can, possibly, be the part of the general scheme of hemophilia diagnosis completely based on the effective PCR test.

The polymerase chain reaction (PCR) was applied in genomic analysis of families at risk for haemophilia A using the intragenic Bel I and Hind III polymorphism in introns 18 and 19, respectively, of factor VIII gene. For the latter the primers derived from exon 19 and 20 sequences allowed to amplify the whole intron 19 resulting in a 730 bp fragment. Hind III restriction of this fragment provides polymorphic fragments of 250 bp or 160 bp and 90 bp respectively. An also occurring 480 bp fragment can be used as internal control to circumvent misdiagnosis due to incomplete or failure of restriction. The Hind III polymorphism was successfully used in prenatal diagnosis of an affected male in the first trimenon of pregnancy. Fetal sexing was also performed by PCR technique using Y specific primers.

Molecular nature of two beta 0-thalassaemia-causing mutations in beta-globin gene in Azerbaijanian population has been elucidated, viz., C-T transition in 39 codon (nonsense mutation) and previously unknown G deletion in 82/83 codons.