Turning the corner from observation to intervention in human genetics

In the early 1990s,shortly after we identified the genetic defect in FMR1 that results in fragile X syndrome（Verkerk et al.,1991）,I attended a conference sponsored by the US National Fragile X Foundation.This biannual meeting mixes families and scientists in a very productive and enlightening way.

Genetically modified human umbilical cord blood cells as a promising strategy for treatment of spinal cord injury

Spinal cord injury （SCI） continues to be a pressing health and social problem. The injury leads to neuronal and glial cell death accompanied by degeneration of nerve fibers. There are currently no particularly effective treatments. SCI causes profound disabil- ity of people affected and has attracted increased attention in the international field of neuroregeneration. For the past two decades, much hope has been placed in cell therapies for the restoration of both structure and function of the injured spinal cord. Embryonic and neural stem cells, olfactory ensheathing cells, microglia-like cells, Schwann cells, mesenchymal stem cells.

Human a Type Genetic Engineering Interference Essence Injection

The highest-level interference essence against virus and turnour genetic engineering medicine is a new type created in the 1980s. Compared with chemical medicines, the interference essence has a special effect in the treatment of viruses and tumours. The human a, type genetic engineering interference essense is prepared by the Institute of Viruses of the Chinese Academy of Preventive Medical Sciences, the Shanghai Vaccine

Amniotic fluid stem cell-based models to study the effects of gene mutations and toxicants on male germ cell formation

Male infertility is a major public health issue predominantly caused by defects in germ cell development. In the past, studies on the genetic regulation of spermatogenesis as well as on negative environmental impacts have been hampered by the fact that human germ cell development is intractable to direct analysis in vivo. Compared with model organisms including mice, there are fundamental differences in the molecular processes of human germ cell development. Therefore, an in vitro model mimicking human sperm formation would be an extremely valuable research tool. In the recent past, both human embryonic stem （ES） cells and induced pluripotent stem （iPS） cells have been reported to harbour the potential to differentiate into primordial germ cells and gametes. We here discuss the possibility to use human amniotic fluid stem （AFS） ceils as a biological model. Since their discovery in 2003, AFS cells have been characterized to differentiate into cells of all three germ layers, to be genomically stable, to have a high proliferative potential and to be non-tumourigenic. In addition, AFS cells are not subject of ethical concerns. In contrast to iPS cells, AFSs cells do not need ectopic induction of pluripotency, which is often associated with only imperfectly cleared epigenetic memory of the source cells. Since AFS cells can be derived from amniocentesis with disease-causing mutations and can be transfected with high efficiency, they could be used in probing gene functions for spermatogenesis and in screening for male reproductive toxicity.

DISTRIBUTION OF ALPHA-1-ANTITRYPSIN VARIANT ETOKYO AND ITS IMPLICATION IN HUMAN POPULATION GENETICS

Ⅰ. INTRODUCTION Alpha-1-antitrypsin (A1AT; locus symbol, PI) is one of the main protease inhibitors in serum. Up to now there are at least 50 A1AT variants that have been found in human populations (Cox, D. W., private communication). The distribution of A1AT variants appears highly racial specificity and geographical variability. This

On Native Origin of the American Indians

There have been controversies over differing opinions in the source of the American Indians. In this paper, the writer criticized the so-called classical theory that the remote ancestors of the American Indians entered America from Asia through the Bering Straits 14,000 ~ 20,000 years ago, worn their “clothes” and carried kindling during the late Paleolithic, no matter how by “boat” across the Bering Sea or by foot through a “Bering Land Bridge” which might once link up Asia and North America during glacial period;and independently proposed a new hypothesis that American Indians might be originated from the Western Rift Valley of North America. On the basis of locus distribution of American ancient human’s remnants, the writer pointed out that American ancient humans might be first originated at Yukon Territory of Canada within the Western Rift Valley of North America (the Basin & Range Province), and then migrated south ward (Yukon Territory → Mojave Desert → Mexico → Peru → Chile). Moreover, American Indians would have long been a presence for 40,000 years, or even 100,000 ~ 200,000 years in the American continents. So far, the logical basis which American Indians came from Asia 14,000 ~ 20,000 years ago was crushed, and derived two inferences: 1) American Indians might be originated from the Western Rift Valley of North America;2) Only the Eskimo might be the mover eastward from Asia, because of their gene B.

Analysis of the HLA-A,-B allele polymorphism in 5844 umbilical cord blood samples taken from Han population of Shandong province

To investigate the HLA-A, -B allele polymorphism in Han population of Shandong province and to explore the possibility to find out the HLA-A,-B-matehed cord blood donors for stem cell transplantation to be used in other area in China, 5844 umbilical cord blood samples were taken from Han population donors of Shandong province, and assayed with PCR-sequence-oligonucleotide （PCR-SSO） assay. In Shandong Hart donors, 20 alleles at HLA-A locus and 46 alleles at HLA-B locus could be detected as revealed in the present study. Among the 20 alleles at HLA-A locus, the most prevalent five alleles included A ＊ 02（0.3041）, A ＊ 11（0. 1443）, A ＊ 24（0. 1434）, A ＊ 30（0.0975） and A 33（0.0859）, while, the alleles with lower gene frequencies included A ＊ 34（0.0006）, A ＊ 25 （0.0005）, A ＊ 66（0.0005）, A ＊ 74（0.0004） and A ＊ （0.0001）. Of the 46 HLA-B alleles detected, the most prevalent five alleles were B ＊ 13（0.1348）, B ＊ 51（0.0713）, B ＊ 62（0.0712）, B ＊ 61 （0.0676） and B ＊ 60（0.0642）; while alleles with lower gene frequencies included B ＊ 77（0.0001）, B ＊ 76（0.0002）, B ＊ 47（0.0003）, B ＊ 42（0.0003） and B ＊ 72（0.0004）. In comparison with those of the other Han population in China, the HLA-A, -B gene frequencies in the umbilical cord blood of Shandong province possess unique distribution features among the investigated populations from various regions of the same race origin, and the differences in various regions of the same race were less than those among the different race. It is evident that the HLA-A,-B alleles of the umbilical cord blood taken in Shangdong province show high degree of polymorphism, and it might be part of those of Northem Han population in China. So, it is reasonable for patients of Northern Chinese to receive HLA class Ⅰ -match transplant of cord blood stem ceils for tissue and organ transplantation from Shangdong umbilical cord blood bank.

Generation of mouse anti-human urate anion exchanger antibody by genetic immunization and its identification

Background Human urate anion exchanger (hURAT1) as a major urate transporter expressed on renal tubular epithelial cells regulates blood urate level by reabsorbing uric acid. Antibody is an important tool to study hURAT1. This study aimed, by genetic immunization, to produce mouse anti-hURAT1 polyclonal antibody with high throughput and high specificity and to detect the location of hURAT1 in human kidney.Methods Human renal total RNA was isolated and the entire cDNA of hURAT1 was amplified by RT-PCR. The sequence of intracellular high antigenicity fragment (A280 to R349) was chosen by prediction software of protein antigenicity, and its cDNA was amplified from cDNA of hURAT1, and then cloned into pBQAP-TT vector to construct recombinant plasmid pBQAP-TT-hURAT1-210 for genetic immunization. Mice were inoculated with this recombinant plasmid and two other adjuvant plasmids, pCMVi-GMCSF and pCMVi-Flt3L, which helped to enhance the antibody’s generation. After four weeks, the mice were sacrificed to obtain the anti-hURAT1 antibody from serum. The antibody was identified by western blot analysis and immunohistochemistry. At the same time, rabbit anti-hURAT1 antibody was produced by protein immunization. The specificity and efficiency between the rabbit and mouse anti-hURAT1 antibody were compared by western blot analysis and immunohistochemistry. Results The entire cDNA of hURAT1 and cDNA of its intracellular high immunogenic fragment were amplified successfully. Recombinant plasmid pBQAP-TT-hURAT1-210 for genetic immunization was confirmed by restriction digestion and sequencing. Both!the mouse anti-hURAT1 antibody and rabbit anti-hURAT1 antibody recognized 58kD hURAT1 and 64kD glycosylated hURAT1 protein bands in western blot. Immunohistochemically, hURAT1 was located at the brush border membrane of renal proximal tubular cells. In addition, the throughput and specificity of the mouse anti-hURAT1 antibody were higher than those of the rabbit anti-hURAT1 antibody.Conclusion Genetic immunization can generate anti-hURAT1 polyclonal antibody of high throughput and specificity.

Population-based frequency of surfactant dysfunction mutations in a native Chinese cohort

Background: Rare mutations in surfactant-associatedgenes contribute to neonatal respiratory distress syndrome.The frequency of mutations in these genes in the Chinesepopulation is unknown.Methods: We obtained blood spots from the GuangxiNeonatal Screening Center in Nanning, China thatincluded Han (n=443) and Zhuang (n=313) ethnic groups.We resequenced all exons of the surfactant proteins-B(SFTPB), -C (SFTPC), and the ATP-binding cassettemember A3 (ABCA3) genes and compared the frequenciesof 5 common and all rare variants.Results: We found minor differences in thefrequencies of the common variants in the Han andZhuang cohorts. We did not find any rare mutations inSFTPB or SFTPC, but we found three ABCA3 mutationsin the Han [minor allele frequency (MAF)=0.003] and 7 inthe Zhuang (MAF=0.011) cohorts (P=0.10). The ABCA3mutations were unique to each cohort;five were novel.The collapsed carrier rate of rare ABCA3 mutations inthe Han and Zhuang populations combined was 1.3%,which is signifi cantly lower than that in the United States(P<0.001).Conclusions: The population-based frequency ofmutations in ABCA3 in south China newborns is signifi cantlylower than that in United States. The contribution of theserare ABCA3 mutations to disease burden in the south Chinapopulation is still unknown.