Objective:To investigate the correlation between root and root canal diameter of maxillary central incisors and age by cone-beam computed tomography(CBCT).Methods:CBCT images of 420 cases of Chinese Han population were divided into 7 age groups as follows:1 5 -24,25 -34,35 -44,45 -54,55 -64,65 -74 and 75 -84(n =60).Root diameter and root canal diameter of maxillary central incisors at the 3 /4 level from the cemenal-enamel junction(CEJ)to root apical were measured.Linear-regression a-nalysis was used to analyze the correlation between root and root canal diameter of the teeth and age,T-test was used to examine the gender difference.Results:Mean root diameter(mm)of the teeth in males and females were 5.81 ±0.445 and 5.53 ±0.489(P <0.05),mean root canal diameter(mm)1 .20 ±0.396 and 0.96 ±0.236(P <0.05),mean of the ratio of root canal diameter and root diameter of the teeth 0.21 ±0.072 and 0.1 7 ±0.043(P <0.05)respectively.There were negative correlations between the ratio of root canal diameter and root diameter of the teeth with age (R2 =0.576,P <0.05).Conclusion:The ratio of root canal diameter and root diameter of maxillary central incisors is negitively correlated with age in Chinese Han population.The decrease of root canal diame-ter in males is more significant than that in females.

Objective To investigate the clinical value of ultrasound markers in screening fetal trisomy 21.Methods From Jan.2001 to Dec.2011,a retrospective study about sonographic information of 138 fetuses diagnosed as trisomy 21 was taken in the First Affiliated Hospital of Sun Yat-sen University.All fetuses were divided into 3 groups:isolated ultrasound markers,non-isolated ultrasound markers,and isolated structural malformations or other abnormalities.The relationship between trisomy 21 and ultrasound markers as well as structural anomalies or other abnormalities was analyzed.Results Sonographic anomalies were detected in 132 fetuses(95.7％,132/138),including ultrasound markers and structural malformations or other abnormalities.One hundred and twenty cases(87.0％,120/138)had ultrasound markers,38(31.7％,38/120)had one marker and 82(68.3％,82/120)had more than one marker (P ＜ 0.01).Fifty-one fetuses(37.0％,51/138)had isolated ultrasound markers and non-isolated markers were found in 69 fetuses(50.0％,69/138).Only 12 fetuses(8.7％,12/138)had isolated structural malformations or other abnormalities.In 20 fetuses on whom the first-trimester ultrasound screening were performed,all had ultrasound markers,95％(19/20)had thickened nuchal translucency and 55％ (11/20)had nasal bone hypoplasia.The most common ultrasound markers on the second-trimester screening were nasal bone hypoplasia,which accounted for 41.9％(52/124)cases,followed by thickened nuchal fold (25.0％,31/124),short fenurs and humerus(24.2％,30/124),echogenic intracardiac focus(16.1％,20/124),mild ventriculomegaly(15.3％,19/124),hyperechoic bowel(12.9％,16/124),mild renal pyelectasis(12.1％,15/124).Furthermore,thc common structural malformations or other abnormalities were as follows:cardiac defects(33.1％,41/124),digestive system(26.6％,33/124).Condusions Ultrasound markers are valuable for screening fetal trisomy 21.The fetuses of trisomy 21 usually had more than one ultrasound markers or associated with other abnormalities.Combinations of ultrasound markers with the results of serum screening and maternal age are necessary for evaluation.

Objective To investigate the prenatal diagnosis and phenotypic assessment strategies for fetal supernumerary marker chromosomes and derivative chromosomes. Methods Five cases of fetal supernumerary marker chromosomes and one case of fetal derivative chromosomes were diagnosed in the First Affiliated Hospital of Sun Yat-Sen University from March 12, 2010 to November 9, 2012 by conventional chromosome banding, fluorescence in situ hybridization (FISH) and spectral karyotyping (SKY). These cases were retrospectively reviewed. Combined with the results of ultrasonography, abnormal phenotypes and pregnancy outcomes were evaluated in these cases. Results All of the five supernumerary marker chromosomes were de novo, in which two were mosaic and the remaining three cases were non-mosaic. Of these five cases, two were type 47, XX+mar and ultrasound indicated abnormal phenotypes. FISH and SKY confirmed that they were derived from chromosome 4 and 22, respectively. The other three cases were marker chromosome with Turner syndrome karyotype (abnormal phenotypes were not found by ultrasound), in which two cases were derived from chromosome Y (by FISH) and one case was identified as ring chromosome X (by FISH and SKY). One de novo derivative chromosome was verified as a product of reciprocal translocation between chromosome 2 and 6 (by FISH and SKY). Induced abortion was performed in all cases between 25 and 32 gestational weeks. Conclusions By combining conventional chromosome banding, FISH and SKY, the origin and content of supernumerary marker chromosomes and derivative chromosomes can be identified. On this basis, clinical phenotype evaluation and genetic counseling may be offered with the ultrasonographic result.

【Objective】 To investigate the epidemiology of HTLV by conducting HTLV nucleic acid detection among voluntary blood donors, so as to provide basis for the decision making of blood screening strategy. 【Methods】 The HTLV blood nucleic acid(NAT) screening platform was established based on the existing NAT for HBV / HCV / HIV screening. HTLV (type 1 + 2) detection was carried out in 5 368 blood donors, and the results were analyzed. 【Results】 No NAT-yielding of HTLV- 1, -2 type was found in a total of 5 368 voluntary blood donor from January to August 2019. 【Conclusion】 Qianxinan, currently, is very low epidemic or non epidemic as none of HTLV infections was found among blood donors and no significant differences in the epidemiology of HTLV were notable between the counties and cities. It, however, still needs further investigation in the future.

OBJECTIVETo explore the reason for discordant results of karyotyping and microarray analysis in a fetus with mosaic tetrasomy 9p.

METHODSAmniocentesis was carried out for a pregnant woman with advanced age for whom ultrasound scan has indicated fetal ventricular expansion, intrauterine growth retardation and persistent upper venous cavity. G-banded karyotyping and single nucleotide polymorphism-based arrays (SNP-array) analysis were performed at the same time.

RESULTSAnalysis of amniocytic chromosome has suggested mosaic tetrasomy 9p (47,XX,+psu idic(9)(q21)[23]/46,XX[27]). While SNP-array has detected a non-mosaic trisomy 9p with a 68.7 Mb duplication at 9p24.3q21.11. The results of the two methods were therefore discordant.

CONCLUSIONSNP-array will analyze genetic material in the form of numbers rather than morphology. For chimeras containing two types of cell lines, when the mosaic rate was close to 50% and the average amount of genetic material of the chimeras was equivalent to the amount of genetic material of non-chimeras, microarray analysis may come to the conclusion of a non-mosaic heteroploidy. Therefore, microarray results for large segment chromosome abnormalities should be combined with the results of G-banded karyotyping for genetic counseling.

Adult ; Amniocentesis ; methods ; Aneuploidy ; Chromosome Banding ; Chromosome Disorders ; diagnosis ; genetics ; Chromosomes, Human, Pair 9 ; Diagnostic Errors ; Female ; Fetal Growth Retardation ; diagnosis ; genetics ; Humans ; Infant, Newborn ; Karyotyping ; Male ; Mosaicism ; Oligonucleotide Array Sequence Analysis ; methods ; Polymorphism, Single Nucleotide ; Pregnancy ; Pregnancy Outcome ; Trisomy

OBJECTIVETo perform molecular cytogenetic study on two fetuses with abnormal ultrasound findings and analyze their genotype-phenotype correlation.

METHODSG-banded karyotyping, single nucleotide polymorphism array (SNP array) and fluorescence in situ hybridization (FISH) were performed on amniotic fluid cells from both fetuses and peripheral blood samples from their parents. Results of SNP array were analyzed with bioinformatics software.

RESULTSG-banded karyotyping failed to detect any abnormalities in both fetuses and their parents. SNP array detected a 2.484 Mb terminal deletion at 17p13.3 [arr[hg19] 17p13.3 (83 035-2 567 405)×1] in fetus 1 and a 3.295 Mb terminal deletion at 17p13.3p13.2 [arr[hg19] 17p13.3p13.2 (83 035- 3 377 560)×1] in fetus 2. Both deletions have overlapped with the critical region of Miller-Dieker syndrome (MDS) and involved candidate genes such as PAFAH1B1, YWHAE and CRK. In addition, SNP array and FISH analyses on the parental peripheral blood samples demonstrated that both 17p13.3 and 17p13.3p13.2 deletions were of de novo origin. Metaphase FISH performed on amniotic fluid cells confirmed the presence of 17p13.3 and 17p13.3p13.2 deletions detected by the SNP array, while metaphase FISH performed on the parents excluded any potential chromosome rearrangements.

CONCLUSIONAbnormal ultrasound features for fetuses with MDS mainly include central nervous system anomalies. SNP array can efficiently detect 17p13.3 microdeletions underlying MDS, and accurately map the breakpoints and involved genes, which may facilitate understanding of the genotype and phenotype correlations for MDS.

Chromosome Banding ; Chromosome Deletion ; Chromosomes, Human, Pair 17 ; genetics ; Classical Lissencephalies and Subcortical Band Heterotopias ; diagnostic imaging ; genetics ; Female ; Fetal Diseases ; diagnostic imaging ; genetics ; Genetic Association Studies ; Genetic Predisposition to Disease ; genetics ; Genotype ; Humans ; In Situ Hybridization, Fluorescence ; Karyotyping ; Phenotype ; Polymorphism, Single Nucleotide ; Pregnancy ; Ultrasonography, Prenatal ; methods

OBJECTIVETo analyze a fetus with increased nuchal translucency and nuchal fold, and to assess the recurrence risk for her family and provide a basis for prenatal diagnosis.

METHODSG-banded karyotyping and single nucleotide polymorphism-based array (SNP-Array) analysis were used to analyze the fetus and her parents.

RESULTSSNP-Array analysis has detected a 41.04 Mb duplication at Xp22.33p11.4 and a 30.51 Mb duplication at 13q31.3q34 in the fetus. G-banding karyotyping indicated that the fetus had a karyotype of 46,X,der(X)(13qter-13q31::Xp11.4-Xp22.3::Xp22.3-Xqter). Her parents had normal results for both G-banding karyotyping and SNP-Array analysis, suggesting that the fetus has carried a de novo derivative chromosome X.

CONCLUSIONSNP-Array combined with G-banding karyotyping is helpful to confirm the composition and connection type of de novo derivative chromosome, which can improve the accuracy of diagnosis and is valuable for the evaluation of recurrence risk.

Adult ; Chromosome Banding ; Chromosome Duplication ; Chromosomes, Human, X ; genetics ; Female ; Fetus ; abnormalities ; metabolism ; Humans ; Karyotyping ; Male ; Oligonucleotide Array Sequence Analysis ; methods ; Polymorphism, Single Nucleotide ; Pregnancy ; Prenatal Diagnosis ; methods ; Sex Chromosome Aberrations

OBJECTIVETo analyze a fetus presenting with complex heart defect and assess the recurrence risk.

METHODSConventional karyotyping, fluorescence in situ hybridization (FISH) and single nucleotide polymorphism-based array (SNP-array) were used to analyze the fetus and his parents.

RESULTSSNP-array has detected a 6.9 Mb microdeletion at 1p36.33-p36.23 in the fetus. Chromosomal and FISH analyses indicated that the father of the fetus had a karyotype of 46,XY,t(1;14)(p36.3;p12), and that the fetus has inherited an abnormal chromosome 1 derived from the paternal translocation.

CONCLUSIONSNP-array combined with GTG banding and FISH can help to detect cryptic translocation, microdeletion or microduplication of chromosomes and is valuable to assess the recurrence risk for the affected family.

Adult ; Chromosome Deletion ; Chromosomes, Human, Pair 1 ; Female ; Heart Defects, Congenital ; genetics ; Humans ; In Situ Hybridization, Fluorescence ; Karyotyping ; Polymorphism, Single Nucleotide ; Pregnancy ; Prenatal Diagnosis

OBJECTIVETo analyze a fetus with abnormal sonographic features and correlated its genotype with phenotype.

METHODSG-banding analysis, single nucleotide polymorphism array (SNP array) and fluorescence in situ hybridization (FISH) were performed for the fetus. Karyotyping and FISH were also carried out for the parents.

RESULTSSNP array detected a 4.4 Mb deletion at 1q44 and a 10.4 Mb duplication at 17q24.3q25.3 in the fetus. Based on the results of SNP array and FISH analysis, the father was diagnosed with a cryptic t(1;17)(q44;q24.3) translocation. The fetus has inherited a der(1)t(1;17)(q44;q24.3) from its father.

CONCLUSIONThe 1q44 deletion and 17q24.3q25.3 duplication may have contributed to the abnormal sonographic features presented by the fetus.

Adult ; Chromosome Deletion ; Chromosomes, Human, Pair 1 ; Chromosomes, Human, Pair 17 ; Female ; Humans ; In Situ Hybridization, Fluorescence ; Polymorphism, Single Nucleotide ; Pregnancy ; Translocation, Genetic ; Trisomy ; genetics ; Ultrasonography, Prenatal

OBJECTIVETo analyze the correlation between atypical neurofibromatosis type 1(NF1) microdeletion and fetal phenotype.

METHODSFetal blood sampling was carried out for a woman bearing a fetus with talipes equinovarus. G-banded karyotyping and single nucleotide polymorphism array (SNP-array) were performed on the fetal blood sample. Fluorescence in situ hybridization (FISH) was used to confirm the result of SNP array analysis. FISH assay was also carried out on peripheral blood specimens from the parents to ascertain the origin of mutation.

RESULTSThe karyotype of fetus was found to be 46, XY by G-banding analysis. However, a 3.132 Mb microdeletion was detected in chromosome region 17q11.2 by SNP array, which overlaped with the region of NF1 microdeletion syndrome. Analyzing of the specimens from the fetus and its parents with FISH has confirmed it to be a de novo deletion.

CONCLUSIONTalipes equinovarus may be an abnormal sonographic feature of fetus with atypical NF1 microdeletion which can be accurately diagnosed with SNP array.

Adult ; Chromosome Banding ; Chromosome Deletion ; Chromosomes, Human, Pair 17 ; genetics ; Craniofacial Abnormalities ; diagnosis ; embryology ; genetics ; Female ; Gene Deletion ; Humans ; Intellectual Disability ; diagnosis ; embryology ; genetics ; Karyotyping ; Learning Disorders ; diagnosis ; genetics ; Male ; Neurofibromatoses ; diagnosis ; embryology ; genetics ; Neurofibromatosis 1 ; diagnosis ; embryology ; genetics ; Pregnancy ; Prenatal Diagnosis