BACKGROUND: The thalassemias are common in southern China. We determined the prevalence of heterozygous carriers of these genetic disorders in Hong Kong and assessed the feasibility of a community-based screening program. METHODS: An educational and screening program for the thalassemias was carried out in three high schools with a total of 2420 students. Seventy-five percent of the students agreed to undergo screening, which consisted of blood counts, hemoglobin electrophoresis, serum ferritin measurements, and DNA analyses. RESULTS: Of the 1800 blood samples tested, 150 (8.3 percent) had microcytosis (mean corpuscular volume, <80 microm3). Ninety students (5.0 percent) were carriers of alpha-thalassemia, of whom 81 (4.5 percent) were carriers of the Southeast Asian type of deletion, in which both alpha-globin genes on the same chromosome 16 are deleted. Sixty-one students (3.4 percent) were carriers of either beta-thalassemia or the mutation coding for hemoglobin E. Six students were carriers of both alpha- and beta-thalassemias. On the basis of these figures, the estimated numbers of pregnancies in Hong Kong in which the fetus is at risk for homozygous alpha-thalassemia and beta-thalassemia major or intermedia are 145 and 80 per year, respectively. In Hong Kong the actual numbers of women referred for prenatal diagnoses of these disorders are approximately 95 and 40 per year, respectively. CONCLUSIONS: Despite the availability of hospital-based screening and prenatal diagnosis for many years in Hong Kong, many women carrying fetuses at risk for thalassemia are not referred for genetic counseling. A community-based program of education, screening, and counseling is needed in Hong Kong and southern China.
BACKGROUND: The thalassemias are common in southern China. We determined the prevalence of heterozygous carriers of these genetic disorders in Hong Kong and assessed the feasibility of a community-based screening program. METHODS: An educational and screening program for the thalassemias was carried out in three high schools with a total of 2420 students. Seventy-five percent of the students agreed to undergo screening, which consisted of blood counts, hemoglobin electrophoresis, serum ferritin measurements, and DNA analyses. RESULTS: Of the 1800 blood samples tested, 150 (8.3 percent) had microcytosis (mean corpuscular volume, <80 microm3). Ninety students (5.0 percent) were carriers of alpha-thalassemia, of whom 81 (4.5 percent) were carriers of the Southeast Asian type of deletion, in which both alpha-globin genes on the same chromosome 16 are deleted. Sixty-one students (3.4 percent) were carriers of either beta-thalassemia or the mutation coding for hemoglobin E. Six students were carriers of both alpha- and beta-thalassemias. On the basis of these figures, the estimated numbers of pregnancies in Hong Kong in which the fetus is at risk for homozygous alpha-thalassemia and beta-thalassemia major or intermedia are 145 and 80 per year, respectively. In Hong Kong the actual numbers of women referred for prenatal diagnoses of these disorders are approximately 95 and 40 per year, respectively. CONCLUSIONS: Despite the availability of hospital-based screening and prenatal diagnosis for many years in Hong Kong, many women carrying fetuses at risk for thalassemia are not referred for genetic counseling. A community-based program of education, screening, and counseling is needed in Hong Kong and southern China.
Authors: X M Xu; Y Q Zhou; G X Luo; C Liao; M Zhou; P Y Chen; J P Lu; S Q Jia; G F Xiao; X Shen; J Li; H P Chen; Y Y Xia; Y X Wen; Q H Mo; W D Li; Y Y Li; L W Zhuo; Z Q Wang; Y J Chen; C H Qin; M Zhong Journal: J Clin Pathol Date: 2004-05 Impact factor: 3.411
Authors: Chunming Ding; Rossa W K Chiu; Tze K Lau; Tse N Leung; Li C Chan; Amy Y Y Chan; Pimlak Charoenkwan; Ivy S L Ng; Hai-Yang Law; Edmond S K Ma; Xiangmin Xu; Chanane Wanapirak; Torpong Sanguansermsri; Can Liao; Mary Anne Tan Jin Ai; David H K Chui; Charles R Cantor; Y M Dennis Lo Journal: Proc Natl Acad Sci U S A Date: 2004-07-09 Impact factor: 11.205
Authors: John J Farrell; Richard M Sherva; Zhi-Yi Chen; Hong-Yuan Luo; Benjamin F Chu; Shau Yin Ha; Chi Kong Li; Anselm C W Lee; Rever C H Li; Chi Keung Li; Hui Leung Yuen; Jason C C So; Edmond S K Ma; Li Chong Chan; Vivian Chan; Paola Sebastiani; Lindsay A Farrer; Clinton T Baldwin; Martin H Steinberg; David H K Chui Journal: Blood Date: 2011-03-08 Impact factor: 22.113