Prenatal diagnosis is an effective approach for preventing birth defects and improving population health.Chromosomal karyotyping,sonography,serum screening,fluorescence in situ hybridization,and PCR-based techniques are examples of current prenatal diagnostic technologies.In recent years,the clinical utility of chromosomal microarray analysis (CMA) have been well demonstrated in postnatal genetic diagnosis and it has been recommended as the first tier test for global developmental delay,mental retardation,congenital multiple anomaly,and autism spectrum disorders.CMA is now also being applied to prenatal testing.However,there are still many unresolved issues regarding the proper use of CMA in prenatal testing.The issues include but not limit to the clinical indications for prenatal CMA,interpretation for copy number variations of unknown significance,selection of array platforms,and genetic counseling.These issues should be addressed in order to properly use CMA in prenatal diagnosis.We believe close collaboration from professionals of different disciplines involved in patient care is necessary to help establish the clinical guideline and best practice recommendation for application of CMA in prenatal diagnosis.

Inherited diseases are characterized with a great variety of clinical entities, complex underlying etiologies, and absence of effective treatment, emerging as one of the significant threats to human′s, esp., the health and wellbeing women and children.It′s long been recognized as a powerful and cost-effective strategy to implement prenatal diagnosis for inherited diseases with an array of advanced molecular diagnostics to reduce the nationwide rate of birth defects.Recently, non-invasive prenatal diagnosis for inherited diseases is increasingly applied in research as well as in clinical practice.Digital PCR is a novel technology characterized with superb sensitivity, high accuracy, and absolute quantitation of DNA, and has demonstrated excellent performance in non-invasive prenatal diagnosis of several hereditary disorders, including spinal muscular atrophy, sickle cell anemia, and hemophilia.It′s believed that digital PCR has more to offer in improving non-invasive prenatal diagnosis of inherited diseases in future.

Due to a wide variety of classification and phenotypes,rare diseases are difficult to be diagnosed in the clinical practice Studies have shown that most rare diseases belong to inherited diseases,so it is particularly important to carry out the genetics research and molecular diagnosis.Next generation sequencing (NGS) technology has the advantages of a high throughput,high sensitivity etc,which is the main research means to identify the pathogenic genes of rare diseases at present.With the development of NGS and the bioinformatics technology,in recent years the whole exome sequencing and targeted panel sequencing have been gradually applied to clinical molecular diagnosis,which is important to increase the accuracy of diagnosis and to improve the therapeutic effect of rare diseases.

Birth defect is increasingly an issue of public health and social concern.Newborn screening is the principal content of 3-tiered system of prevention and control for birth defects in China,which plays an important role in promotion of children's health and welfare.Widespread application of mass spectrometry,esp.,tandem mass spectrometry in newborn screening of inherited metabolic diseases has greatly contributed to the increased detection capability and efficiency.Low and medium throughput molecular diagnostic techniques including PCR,Sanger sequencing,high resolution melting analysis,and multipleligation dependent probe amplification are widely applied in diagnosis and discrimination of inherited metabolic diseases.Application of next generation sequencing in newborn screening is emerging,and will undoubtedly revolutionize the arena of newborn screening in future.However,vigorous validation and performance evaluation are warranted before it's applied in newborn screening for inherited metabolic diseases.

High-resolution melting analysis ( HRMA/HRM ), a simple, rapid, flexible, inexpensive closed tube approach with high sensitivity and specificity has been one of the most widely used molecular diagnostic techniques in clinicalas well as in research settings .Recently, rapid development ofinstruments , DNA dyes and analysis software significantly enhance the sensitivity , specificity and accuracy of HRM,providing a fast, efficient and economic molecular diagnostic platform for molecular diagnosis of inherited disease , molecular profiling and target therapy of cancer , identification of pathogen , as well as individualized medicine.

Objective To investigate and understand the reference value range of hematological parameters for peripheral blood routine in preschool children from Shanghai.Methods The Sysmex XS-800i automated hematology analyzer and the original rea-gents were used to measure the hematological parameters in peripheral blood samples collected from 7 692 healthy preschool chil-dren aged 2-6 years in Shanghai,including white blood cells(WBC),red blood cells(RBC),platelet(PLT)count,hemoglobin(Hb), hematocrit(HCT),mean corpuscular volume(MCV),mean corpuscular hemoglobin(MCH)and mean corpuscular hemoglobin con-centration(MCHC);the various parameters in different age groups were collected and statistically processed to establish the refer-ence intervals for each parameter.Results In the blood routine among preschool children in Shanghai,there were statistically signif-icant differences in all parameters except WBC and PLT count between sexes among preschool children in Shanghai(P <0.05).The reference intervals of hematological parameters obtained in this investigation were obviously differed from those offered by the man-ufacturer.However,compared with those from the related reports,the difference existed in partial parameters,the upper limit of WBC count was highest compared with the results from some areas,while the reference value ranges of MCV,MCH and MCHC were higher than those of other area study results.Conclusion The independent blood routine medical reference value range for preschool children in Shanghai should be established and the influence of the factors of gender,instrument and reagents also should be taken into consideration in establishing the reference value range.

Copy number variations in the human genome,one of the causes of complex diseases and genetic diseases,can lead to genomic disorders.As these diseases are difficult to diagnose,it is significantly meaningful to conduct genetic researches and molecular diagnosis.Chromosomal microarray can be used to detect copy number variations on a genome-wide scale.With the advantage of high throughput and resolution,chromosomal microarray is perceived as an important means of identifying copy number variations in genomic disorders.As technology advancements of chromosomal microarray and accumulations of clinical experiences,chromosomal microarray has played a significant role in etiological diagnosis of multiple malformations,mental retardation and autism.

ObjectiveTo establish an effective method for F9 gene mutation detection by using high resolution melting ( HRM ) curve analysis.Methods Peripheral blood samples of 55 hemophilia B (HB) patients were collected from Shanghai Ruijin Hospital during January 2005 to June 2010.Genomic DNA was extracted from the peripheral blood.PCR amplification combined with sequencing was used to identify the F9 gene mutations in 40 patients.HRM assay was established on the 21 DNA samples with known mutations in exonl to exon7 of F9 gene.Mutation scanning of exonl to exon7 by HRM combined with direct sequencing of exon8 was used in the molecular diagnosis of 15 HB patients with unknown F9 gene mutations.ResultsF9 gene mutation was detected in each of the 40 HB patients by direct sequencing.By HRM,the different melting curve patterns were identified in 19 out of 21 cases.The detection rate was about 90％.Through mutation scanning of exonl to exon7 by HRM combined with direct sequencing of exon8,F9 gene mutations were detected in all the 15 HB patients with unknown F9 gene mutations.Thirty-four F9 gene mutations had been identified in the 55 HB patients.ConclusionsA new strategy of HB genetic diagnosis,scanning mutations of exonl to exon7 combined with DNA sequencing of exon8 of F9 gene,is established in this study.The new strategy is efficient and reliable.

Objective To establish the pediatric reference intervals for Troponin Ⅰ and Creatine kinase-MB (CK-MB).Methods Healthy children (223 boys and 162 girls) aged from 7 months to 12 years old were studied.Blood specimens were collected and centrifuged,all serum samples were kept refrigerated below-70 ℃.Troponin Ⅰ and CK-MB were measured on the UniCel DxI 800 immunoassay system (Beckman Coulter) on the same day.Nonparametric statistics was used to estimate the 99th percentile reference intervals.Results The children were divided into three groups (group A 128 cases; group B 128 cases;group C 129 cases) according to age.The upper reference limits for CK-MB were dependent of age,and the group A (7 months-1 years) was shown to be 13.41 μg/L,the group B (2-3 years) was shown to be 9.35 μg/L,the group C (4-12 years) was shown to be 5.48 μg/L.The upper reference limit for Troponin Ⅰ was independent of age or gender and shown to be 0.01 μg/L among 385 children.Conclusions Pediatric reference intervals for Troponin Ⅰ and CK-MB have been defined in healthy children at a relevant age group (7 months-12 years).It is effective for clinical diagnosis and treatment of myocardial damage for children by determining reference intervals for Troponin Ⅰ and CK-MB.

Objective To establish the method of gene mutation screening for HME and investigate the relationship between genotype and clinical phenotype in HME patients. Methods Fifteen cases of HME probands were divided into the following four subgroups: mild (M) and severe ( Ⅰ S, Ⅱ S, Ⅲ S) according to the clinical diagnosis. DNA samples were obtained from the probands and family members. All of the EXT1 and EXT2 gene exons and their boundary sequences were amplified by PCR, and sequenced by directsequencing. Then the relationship between the genotypes and clinical phenotype was analyzed. Results Among the fifteen cases of HME probands, nine harbored EXT1 gene mutation, while the other 6 were positive for EXT2 gene mutation. Moreover, six novel mutations in EXT1 gene, including I8 + 2T ＞ G, c. 1182delG,c. 1108G ＞T(p. E370X) ,c. 335delA,c. 361C ＞T(p. Q121X) and c. 1879_1881delCAC were identified. In 9 patients with EXT1 gene mutation, 2 (22. 2% ) were M-type, 2 (22. 2% ) were Ⅰ S -type, 4 (44. 4% )were Ⅱ S-type,and 1 ( 11.1% ) was ⅢS-type. Whereas, 5 cases (83.3%) were M-type and only one case was Ⅱ S-type( 16. 7% ) in 6 patients with EXT2 gene mutation. Conclusions An accurate and simple gene diagnostic method for HME was established. Six novel EXT1 gene mutations, including I8 + 2T ＞ G,c. 1182delG, c. 1108G ＞T(p. E370X), c. 335delA, c. 361C ＞T(p. Q121X)and c. 1879_1881delCAC were identified as well. The clinical phenotype of the patients with EXT1 gene mutation was more severe compared to those with EXT2 gene mutations.