植入前遗传学诊断的安全性和可靠性探讨

植入前遗传学诊断(preimplantation genetic diagnosis,PGD)是在胚胎植入前对配子或体外受精胚胎进行遗传学分析的一项诊断技术,目的在于从源头预防遗传性疾病的发生,从而改善有遗传性疾病高风险夫妇的妊娠结局.近年来,随着分子生物学技术的进步,越来越多遗传性疾病的发生机制被阐明,PGD的诊断范围逐渐扩展,其应用周期数也日益增多.新技术的开展如比较基因组杂交及其微阵列提高了PGD诊断的准确性.然而,这项技术的安全性问题也引起了人们高度重视.作者从透明带开孔技术、不同时期胚胎活检、胚胎活检细胞数目以及遗传分析技术的可靠性等方面对PGD的安全性进行了探讨.     

植入前遗传学诊断的安全性和可靠性探讨

植入前遗传学诊断(preimplantation genetic diagnosis,PGD)是在胚胎植入前对配子或体外受精胚胎进行遗传学分析的一项诊断技术,目的在于从源头预防遗传性疾病的发生,从而改善有遗传性疾病高风险夫妇的妊娠结局.近年来,随着分子生物学技术的进步,越来越多遗传性疾病的发生机制被阐明,PGD的诊断范围逐渐扩展,其应用周期数也日益增多.新技术的开展如比较基因组杂交及其微阵列提高了PGD诊断的准确性.然而,这项技术的安全性问题也引起了人们高度重视.作者从透明带开孔技术、不同时期胚胎活检、胚胎活检细胞数目以及遗传分析技术的可靠性等方面对PGD的安全性进行了探讨.     

植入前遗传学诊断的安全性和可靠性探讨

植入前遗传学诊断(preimplantation genetic diagnosis,PGD)是在胚胎植入前对配子或体外受精胚胎进行遗传学分析的一项诊断技术,目的在于从源头预防遗传性疾病的发生,从而改善有遗传性疾病高风险夫妇的妊娠结局.近年来,随着分子生物学技术的进步,越来越多遗传性疾病的发生机制被阐明,PGD的诊断范围逐渐扩展,其应用周期数也日益增多.新技术的开展如比较基因组杂交及其微阵列提高了PGD诊断的准确性.然而,这项技术的安全性问题也引起了人们高度重视.作者从透明带开孔技术、不同时期胚胎活检、胚胎活检细胞数目以及遗传分析技术的可靠性等方面对PGD的安全性进行了探讨.

Abstract：

Preimplantation genetic diagnosis (PGD) refers to a procedure to genetically analyze embryos prior to implantation, in order to prevent the occurrence of specific inherited disorders before conception and improve the outcome of high-risk pregnancy with genetic disorders. In recent years, with the advance of molecular biology techniques, more and more genetic diseases have been elucidated, and PGD has been gradually expanding its scope and applications. New technologies, such as microarray comparative genomic hybridization (array CGH), are developed to improve the accuracy of diagnosis. However, the safety of this procedure has aroused great attention. In this article, authors will review the safety of zona opening procedures, different biopsy procedures at different stages, and removal of one or two cells from cleavage-stage embryos. The reliability of genetic analysis technologies will be discussed as well.     

植入前遗传学诊断方法的现状和进展

植入前遗传学诊断（preimplantation genetic diagnosis, PGD） 是辅助生育技术与分子生物学技术相结合而形成的一种产前诊断技术,目的是减少携带遗传疾病的胚胎移植.同时减少孕妇反复流产或引产的痛苦.PGD常用的检测方法为：聚合酶链反应（PCR）和荧光原位杂交（FISH）.本综述就这两种技术在PGD中应用及存在的问题做一总结.     

紧密连锁的多态性位点在β地中海贫血植入前遗传学诊断中的应用

目的 探讨与β珠蛋白基因紧密连锁的多态性位点HumTH01在β地中海贫血（β地贫）植入前遗传学诊断（preimplantation genetic diagnosis，PGD）中的作用。方法 对4例已出生重型β地贫患儿的、双方均为β地贫基因携带者的夫妇进行了6个周期的PGD治疗，应用多重巢式PCR同时检测β珠蛋白基因及HumTH01基因，选择健康的胚胎移植入子宫。结果 6个周期共活检44个胚胎，获得44个卵裂球，其中41个卵裂球扩增成功，35个胚胎经PCR分析后获得明确诊断，移植了14个胚胎，获得1例临床妊娠。孕17周时经脐带血穿刺，证实为完全正常胚胎，现已出生一正常女婴。单个卵裂球平均扩增效率为89．7％，等位基因脱扣（allele drop-out，ADO）率为14．4％。HumTH01基因可以帮助检测出ADO及污染的发生。结论 本研究为国内首次报道应用多重巢式PCR同时检测β珠蛋白基因及HumTH01基因对β地贫进行植入前遗传学诊断并成功获得临床妊娠。在PGD中同时检测与β珠蛋白基因紧密连锁的多态性位点可以降低PGD中由于ADO及污染造成的误诊的风险。     

单基因遗传病的植入前遗传学诊断研究进展

近十多年来，单基因遗传病的植入前遗传学诊断（PGD）已取得了显著的成绩，其基本技术包括胚胎活检，PCR和FISH。本文就PGD的研究概况，活检标本来源，以PCR技术为基础的各类诊断技术的研究进展，影响PGE准确性的原因及未来的发展作一综述。     

一例嵌合型18三体少精子症患者精染色体分析及植入前遗传学诊断

目的 分析1例嵌合型18三体少精子患者精子18、X、Y染色体数目畸变并进行植入前遗传学诊断(preimplantation genetic djagnosis,PGD).方法 采用G带及荧光原位杂交(fluorescence in situ hybridjzation,FISH)对中期分裂相进行分析,应用三色探针CEP18、CEPY、Tel Xq/Yq对患者精子进行FISH分析,同时以1名染色体正常男性的正常精液作为对照,并对嵌合型18三体患者进行PGD.结果 患者精子18二体率、性染色体二体率和二倍体率分别为0.63%、0.94%和0.87%,与对照组相比(0.16%、0.35%、0.31%)差异有统计学意义.患者进行1个PGD周期的治疗、活检4个胚胎,移植正常的XY1818、XX1818各1胚胎后获得临床妊娠.结论 精子FISH分析可为其提供更准确的遗传咨询及指导植入前遗传学诊断,FISH-PGD可有效地应用于嵌合型18三体的植入前遗传学诊断.     

跨断裂点探针及其在胚胎植入前遗传学诊断研究进展

植入前遗传学诊断(preimplantation genetic diagnosis,PGD)是产前诊断的一种新方案,理论上可避免以往产前诊断有异常而不得不终止妊娠的遗憾。染色体异常是PGD的很重要一部分,其中的染色体结构异常是。PGD的难点之一。用目前商业化的探针不能区分正常和平衡易位的核型,针对各个病例的跨断裂点探针能区分这两种核型。本文就跨断裂点探针的技术路线、应用实例及其应用前景作一简要介绍。     

单基因遗传病的植入前遗传学诊断研究进展

近十多年来 ,单基因遗传病的植入前遗传学诊断 (PGD)已取得了显著的成绩 ,其基本技术包括胚胎活检、PCR和FISH。本文就 PGD的研究概况、活检标本来源、以 PCR技术为基础的各类诊断技术的研究进展、影响 PGD准确性的原因及未来的发展作一综述     

跨断裂点探针及其在胚胎植入前遗传学诊断研究进展

植入前遗传学诊断(preimplantation genetic diagnosis，PGD)是产前诊断的一种新方案，理论上可避免以往产前诊断有异常而不得不终止妊娠的遗憾。染色体异常是PGD的很重要一部分，其中的染色体结构异常是PGD的难点之一。用目前商业化的探针不能区分正常和平衡易位的核型，针对各个病例的跨断裂点探针能区分这两种核型。本文就跨断裂点探针的技术路线、应用实例及其应用前景作一简要介绍。     

Renal dysplasia and asplenia in two sibs

A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.     

Schizophrenia in a North Swedish geographical isolate, 1900–1977. Epidemiology, genetics and biochemistry

Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc² (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.     

The dominant diseases of modernized societies as omega-3 essential fatty acid deficiency syndrome: Substrate beriberi

About 1900, modern food selection and processing caused widespread $\text{epidemics}$ of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a $\text{panh}$ypovitaminosis B, i.e., a mixture of $\text{substrate}$ beriberi and $\text{substrate}$ pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse $\text{endemic}$ disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for $\text{primates}$. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.     

What will studies of Fulani individuals naturally exposed to malaria teach us about protective immunity to malaria?

There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.     

'Very sore nights and days': the child's experience of illness in early modern England, c.1580-1720

Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.     

Guidelines for the Validation and Use of Immunoassays for Determination of Introduced Proteins in Biotechnology Enhanced Crops and Derived Food Ingredients

Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.     

HLA in North Colombia Chimila Amerindians

HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.     

Ultracryotomy: development and application (with examples from the yeast cytology) (author's transl)

The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.     

The universal muscular chamber. A basic unit of the genitourinary, cardiovascular, gastro-intestinal, skeletal, cutaneous, respiratory and other systems, endocameral hypertension; and spasm, the key to their idiopathic diseases and arthropathies

Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions.