Relationship of vascular endothelial growth factor gene polymorphisms with retinopathy of prematurity in pre-term infants / 中华实验眼科杂志

Background Statistic data revealed that different retinopathy of pre-term infants have different susceptibility to retinopathy of prematurity (ROP),which may be associated with polymorphism of vascular endothelial growth factor(VEGF) gene.Objective This study was to determine the association of polymorphisms of VEGF gene with the risk for ROP.Methods This research was approved by Ethics Committee of Hunan Children's Hospital,and written informed consent was obtained from the parents of patients.A prospective case-controlled study was designed.Ninety-nine ROP patients in Hunan Children' s Hospital and 88 pre-termed children without ROP were included from January,2006 to December,2009.Thirty-nine patients who received retinal photocoagulation or cryotherapy were included as the treatment group,and 60 untreated but spontaneously regressed ROP patients as the non-treatment group.No significant differences were seen in demography between with the ROP group and the without ROP group,or between the treatment group and the non-treatment group (all P＞0.05).2 mL of peripheral blood was collected for the extraction of DNA.Gene polymorphisms of VEGF-A+405 and VEGF-A936 were detected using the pyrosequencing method.Results No significant difference was found in the frequencies of the VEGF-A+405 gene polymorphisms between the ROP group and without ROP group (P =0.071,OR =0.675,95 ％ CI =0.444-1.026).Also no significant difference was found in the frequencies of the VEGF-A936 gene polymorphisms between with the ROP group and without the ROP group (P =0.118,OR =0.768,95 ％ CI=2.823-4.614).However,the frequencies of the VEGF-A+405 gene polymorphisms were significantly higher in the ROP treatment group than the non-treatment group (P＜0.01,OR--0.857,95 ％ CI =5.239-14.024),and VEGF-A936 gene polymorphisms was also significantly higher in the ROP treatment group than the non-treatment group (P =0.000,OR =3.609,95 ％ CI =0.711-0.829).Conclusions There is no association between the VEGF-A+405/VEGF-A936 single nucleotide polymorphism with the risk of ROP,but polymorphisms of VEGF gene may be correlated with the prognosis of ROP.The carrier of VEGF-A +405 /VEGF-A936 allele is more susceptible to ROP progression.

Analysis of ring chromosome 9 syndrome with fluorescence in situ hybridization / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the mechanism of the ring chromosome 9 formation by cytogenetic analysis of one case affected with ring chromosome 9 syndrome.</p><p><b>METHODS</b>Routine chromosome GTG-binding analysis and dual-color fluorescence in situ hybridization (FISH) with TelVision 9p and 9q probes were applied to characterize the case.</p><p><b>RESULTS</b>The G-binding revealed that the patient had ring chromosome 9 with the following karyotype: 45,X,-9/46,XX,r(9)(p24q34)/46,XX,r(9;9)(p24q34;p24q34)[4/92/4]. The dual-color FISH analysis with TelVision 9p and TelVision 9q probes failed to detect a hybridization signal on the ring chromosome in the case, which indicated that at least 115 kb were deleted on the terminal 9p and 95 kb were deleted on the terminal 9q. Comparing to the cases reported in the literatures, our patient shared some common features of the 9p- and 9q- syndrome.</p><p><b>CONCLUSION</b>The clinical features of patients with identical r(9) breakpoints present variable phenotypes. The possible cause might be the submicroscopic variation in the deletion breakpoints, variation in the ring stability, the modification of the expression of the deleted by the individual's genetic background, or the effect of changes in the fetal environment. The haploinsufficiency of genes located in the deleted regions may play critical roles in the patient phenotype as well.</p>

Analysis of the small supernumerary marker chromosome in Turner syndrome with 45, X/46, X, + mar karyotype / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To identify the origin and study the morphology of small supernumerary marker chromosome (sSMC) in Turner syndrome with 45, X/46, X, + mar karyotype.</p><p><b>METHODS</b>Using the conventional chromosome G-banding technique, 10 cases of Turner syndrome with 45, X/46, X, + mar chromosome karyotype were obtained, dual-color fluorescence in situ hybridization was applied to study the origin and morphology of the sSMC.</p><p><b>RESULTS</b>In the 10 cases of Turner syndrome with 45, X/46, X, + mar karyotype, the sSMC of 7 cases was derived from X chromosome [sSMC(X)], the sSMC of 2 cases was derived from Y chromosome [sSMC(Y)] and the remaining 1 case was derived from the autosome. There were 4 cases of ring(r) chromosomes and 3 of centric minutes (min) in the 7 sSMC (X) cases. In the 2 sSMC(Y), one case was dicentric (dic) and the other was centric minute (min). The sSMC originated from the autosome was a centric minute (min).</p><p><b>CONCLUSION</b>The origin of sSMC of Turner syndrome with 45, X/46, X, + mar karyotype was almost all from sex chromosomes, and rarely from autosomes. sSMC can exist as isodicentric, ring, or centric minute. The molecular cytogenetic features of the sSMC can provide useful information for genetic counseling, prenatal diagnosis and treatment of the Turner syndrome patients with a 45, X/46, X, + mar karyotype.</p>

Cytogenetic analysis and phenotype location analysis on the karyotype of a ring chromosome 21 syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To search the forming cause and the correlation between the clinical phenotype and chromosome band by the cytogenetic analysis on a case of ring chromosome 21 syndrome.</p><p><b>METHODS</b>Identification and location of 21 ring chromosome were performed with the G-banding, C-banding, N-banding, high-resolution banding and fluorescence in situ hybridization (FISH) techniques.</p><p><b>RESULTS</b>It was found that the karyotypes of the patient's parents are normal. The patient's karyotype is 46,XY, r(21)[91]/46,XY,r(21;21)(p11q22.3;p11q22.3) [5]/45,XY,-21[4].</p><p><b>CONCLUSION</b>The clinical phenotype of ring chromosome 21 syndrome is related to the deletion of distal segment of 21q, and the abnormal sexual development of male is related with the deletion of 21q22.3.</p>