Midtrimester Amniocentesis for Prenatal Diagnosis

PROPOSE: To analyze the indications and cytogenetic results of midtrimester amniocentesis. MATERIAL AND METHODS: This study reviewed 2,523 cases of midtrimester prenatal genetic amniocentesis performed at MizMedi Hospital between January 2000 and December 2007. RESULTS: The most frequent indication for midtrimester amniocentesis was advanced maternal age (45.9%), followed by positive serum markers (29.9%). Chromosomal aberrations were diagnosed in 110 cases (4.4%), for which numerical aberration accounted for 38 cases (34.5%), structural aberration accounted for 65 cases (59.1%), and mosaicism accounted for 7 cases (6.4%). Among the autosomal aberrations, there were 20 cases of trisomy 21 and 8 cases of trisomy 18. With respect to structural aberrations, there were 14 cases of reciprocal translocation and 8 cases of robertsonian translocation. The frequencies of chromosomal aberrations according to the indication were highest in individuals with a family history of chromosome abnormality 14.0% (8/57) followed by previous congenital anomaly 5.9% (2/34). CONCLUSION: Midtrimester amniocentesis is an effective tool for prenatal diagnosis. Indications such as advanced maternal age, maternal serum markers, and ultrasound are important for predicting abnormal fetal karyotypes.

The spectrum of 5p deletion in Korean 20 patients with Cri du chat syndrome

PURPOSE: Cri-du-Chat syndrome (CdCs) is a rare but clinically recongnizable condition with an estimated incidence of 1:50,000 live births. The clinical characteristics of the syndrome include severe psychomotor and mental retardation, microcephaly, hypertelorism, hypotonia, and slow growth. Also the size of the chromosome 5p deletion ranges were known from the region 5p13 to the terminal region. In this study, we report the spectrum of 5p deletion in Korean 20 pts. with CdCs and genotype-phenotype associations in CdCs. METHODS: In order to delineate genotype-phenotype correlation, molecular cytogenetic studies including GTG banding and clinical characterization were performed on Korean 20 pts with CdCs including parents. CGH array and Fluorescence in situ hybridization (FISH) analysis were used to confirm a terminal deletion karyotype and map more precisely the location of the deletion breakpoint. RESULTS: Molecular analysis of the spectrum of 5p deletion revealed 9 pts (45%) with a del (5)(p14), 7 pts. (35%) a del (5)(p13), 3 pts. (15%) a del (5)(p15.1) and 1 pt. (5%) a del (5)(p15.2) in 20 pts with CdCs. 4(20%)pts were identified to have additional chromosome abnormalites of deficiency and duplication involving chromosomes of 6, 8, 18, & 22. Parental study identified 3 familial case (2 paternal and 1 maternal origin) showing parents being a balanced translocation carrier. And the comparison study of the deletion break points among these 20 pts. with their phenotype has showed the varying clinical pheno-types in the CdCs critical region. CONCLUSION: The characterization of 5p deletion including parental study may help to delineate the genotypephenotype correlation in CdCs. Also these molecular cytogenetic analyses will be able to offer better information for accurate genetic diagnosis in CdCs and further make possible useful genetic counseling in pts. and family.

National survey for genetic counseling and demands for professional genetic counselor

PURPOSE: The necessity of professional non-MD genetic counselor has been recently emphasized in a medical field. By conducting a national survey on the demands for generic counseling and professional non-MD generic counselor, we can make a long-term master plan to execute the educational program for professional genetic counselors and indeed promote genetic counseling in Korean health care service in a systemic manner. METHODS: The survey has been conducted from September 3rd to October 4th of 2007 in a way of e-mail, telephone interview, fax, and direct contacts. It's targets were senior researchers and professors in medical and non-medical institutions, policy makers, research institutions or foundations. The survey questions consist of 16 questionnaires. RESULTS: As a result of survey, 102 of 650 people responded. 80% of respondents indicated that genetic counseling is needed as a health care service and 34% among them considered it as "the most needed". In addition, 77% of the respondents showed that, it is necessary to have a professional non-MD genetic counselor with a master degree or higher in the field of medical genetics and among them 29% thought it as "the most necessary". A 77% of respondents considered that the cost of genetic counseling should be covered by health insurance and among them, 29% answered "strongly agreed". A 56% of respondents chose the answer of "They have a plan to hire the professional non-MD genetic counselor" in their institution, and among them 71% selected "within 5 years" in terms of when to hire. Also, they tend to expect the role of the professional non-MD genetic counselor to be not only "genetic counselor" (60%), but also "researcher" (42%), "educator" (18%) and "clinical laboratory coordinator" (19%). CONCLUSION: The 102 of 650 people responded to the survey. Based upon the nationwide survey over the needs on genetic counseling in health care service and demands on the professional non-MD genetic counselor, systematic educational program for the genetic counseling, with reimbursement coverage for counseling service by health insurance should be emphasized in development of a master plan.