Genetic counseling

Medical professionals and the public are rapidly becoming aware of the overwhelming influence that an individual's genetic constitution has on fetal health and mortality, congenital malformations, cancer and other chronic diseases. Great strides have been made in recognizing and understanding modes of inheritance that had not previously been well described. Besides single-gene disorders, genetic conditions are known to be caused by a variety of different mechanisms: chromosome microdeletions and fragility, multifactorial inheritance, mitochondrial genes, triplet repeat expansions, imprinting, and uniparental disomy. Because of the complexity of genetic information, an extensive discussion is often necessary to sort out advertising, news information, and personal health concerns to enable individuals to make decisions for themselves about the various options available for testing and treatment. Genetic counseling has developed as a discipline in response to the need to educate patients, families and professionals about genetic mechanisms and their application in health care. In the future, we anticipate that the emphasis will be on primary care physicians as health-care managers, and genetic counselors will be required to educate individuals about their personal risks of inherited disorders and the implications for future generations. Genetic counseling is a process of medical education based upon empathy, patient autonomy and confidentiality in an atmosphere of empathy, support and understanding. This profession combines the knowledge of complex medical and genetic theory with the skills of a concerned, supportive counselor.     

Hereditary polyposis coli. II. Genetic counseling

The problems of genetic counseling in hereditary polyposis coli (HPC)(taken as the type of the age-dependent dominant mendelian trait) are discussed in some detail. They are threefold: first to formalize, for purposes of decision, the total penalty (the "fardel") typically imposed by the disorder for each case, and how it may be modified by treatment; second, to determine the logical issues involved in making probability statements in the face of the uniqueness of each case; third, to use to best advantage the information on the pattern of onset to assess the probability that a person, at risk but not so far affected, does in fact harbor the gene. The third problem points up the need for a formal model of the pathogenesis and its implications for the pattern of onset and the sensitivity of the assessment to the assumptions of the model, especially where one has to rely on cross-sectional, as distinct from longitudinal, data.     

假性甲状旁腺功能减退症1a型基因诊断二例报道

假性甲状旁腺功能减退症（preudohypoparathyroidism,PHP）简称假性甲旁减或Seabright-Bantam综合征，是一种罕见的家族性甲状旁腺疾病，临床表现主要以靶器官对甲状旁腺激素抵抗为特征。通常有低钙血症，高磷血症和循环中甲状旁腺素（parathyroid hormone,PTH）增加，临床上PHP分为Ⅰ型和Ⅱ型，前者又分为Ⅰa,Ⅰb和Ⅰc3种类型。     

假性甲状旁腺功能减退症Ⅰa型基因诊断二例报道

假性甲状旁腺功能减退症(pseudohypoparathyroidism,PHP)简称假性甲旁减或Seabright-Bantam综合征,是一种罕见的家族性甲状旁腺疾病.临床表现主要以靶器官对甲状旁腺激素抵抗为特征,通常有低钙血症、高磷血症和循环中甲状旁腺素(parathyroid hormone,PTH)增加.临床上PHP分为Ⅰ型和Ⅱ型,前者又分为Ⅰa、Ⅰb和Ⅰc 3种类型.其中Ⅰa型又称为Albright遗传性骨营养不良症(Albright's hereditary osteodystrophy,AHO).AHO是一类遗传性的综合征,具有特征性的体形,如身材矮小、圆脸、肥胖、齿列发育不良、短指和(或)短趾畸形等[1].     

青年聋人的遗传咨询与婚配指导

目的 利用基因诊断技术分析青年聋人的分子致病机制,为青年聋人在婚前提供准确的遗传咨询与婚配指导.方法 来自云南与贵州的217例青年聋人参加了此研究,经询问病史、体格检查及听力学检查之后,采集受检者外周血并提取DNA,进行GJB2全基因分析、SLC26A4常见位点突变和线粒体基因1555位点突变检测.根据基因检测结果,结合病史与查体信息,为青年聋人提供遗传信息与婚配生育指导.结果 217例青年聋人中,76例(35.0%)耳聋基因检测结果阳性.23例(10.5%)为线粒体基因A1555G点突变,其中女性10例,建议患者及家庭中所有母系成员,特别是女性患者的所有后代,应终生绝对禁止使用氨基糖苷类抗生素;28例(12.9%)为GJB2纯合或复合突变;5例(2.3%)为GJB2杂合突变;19例(8.8%)为SLC26A4纯合或复合突变;1例(0.5%)为SLC26A4杂合突变.建议GJB2与SLC26A4阳性患者在婚配前其配偶要进行相应基因的检测,避免与相同基因致聋者婚配;同时向SLC26A4阳性患者提出具体的注意事项.结论 青年聋人通过耳聋基因诊断可以得到更加科学准确的遗传咨询和婚配指导.     

一个血小板减少伴桡骨缺失综合征家系的遗传学研究及产前诊断

目的 对一个血小板减少伴桡骨缺失(TAR)综合征家系进行遗传学病因分析及产前诊断.方法 采用染色体微阵列分析(CMA)、荧光定量聚合酶链反应(qPCR)和Sanger测序对一个TAR综合征家系进行基因突变分析.提取先证者、父母及姐姐4名家系成员的基因组DNA,行CMA、qPCR和Sanger测序,明确致病突变后对胎儿行...