Aim: Thalassaemia is a good candidate disease for control by preventive genetic programmes in developing countries. Accurate population frequency data are needed for planning the control of thalassaemia in the high risk Guangdong Province of southern China. Methods: In total, 13 397 consecutive samples from five geographical areas of Guangdong Province were analysed for both haematological and molecular parameters.Results: There was a high prevalence of carriers of a thalassaemia (8.53%), b thalassaemia (2.54%), and both a and b thalassaemia (0.26%). Overall, 11.07% of the population in this area were heterozygous carriers of a and b thalassaemia. The mutation spectrum of a and b thalassaemia and its constitution were fully described in this area. This study reports the true prevalence of silent a thalassaemia in the southern China population for the first time. In addition, two novel mutations that give rise to a thalassaemia, one deletion resulting in b thalassaemia, and a rare deletion (22 THAI allele) previously unreported in mainland China were detected. The frequency of the most common mutation, the Southeast Asian type of deletion (22 SEA , accounting for 48.54% of all a thalassaemias) was similar to the total of two a + thalassaemia deletions (2a 3.7 and 2a 4.2 , accounting for 47.49% of a thalassaemia). Conclusion: Both a and b thalassaemia are widely distributed in Guangdong Province of China. The knowledge gained in this study will enable the projected number of pregnancies at risk to be estimated and a screening strategy for control of thalassaemia to be designed in this area.

Background: IVS-II-5 G>C (HBB: c.315+5 G>C) is a rare β-thalassemia mutation. However, there is no clear evidence regarding the effect of this defect or co-inheritance of other β-thalassemia mutations on phenotypes. Methods: The clinical phenotypes associated with compound heterozygosity for the IVS-II-5 G>C mutation with other β-thalassemia mutations, together with the potential effect of the genetic modifiers α-thalassemia were studied in 13 patients. Analyses of red cell indices, hemoglobin component, iron status, and α-globin genes were carried out in 19 heterozygotes. Results: Next-generation sequencing of 24 undiagnosed patients with thalassemia major (TM) or thalassemia intermedia (TI) identified 13 carriers of the IVS-II-5 G>C mutation. There was a wide spectrum of phenotypic severity in compound heterozygotes and 6 (46.2%) of 13 were transfusion dependent. Analysis of 19 heterozygotes indicated that most were hematologically normal without appreciable microcytosis or hypochromia, and approximately half had normal hemoglobin A2 levels at the same time. Conclusion: Compound heterozygotes for IVS-II-5 G>C and other severe β-thalassemia mutations are phenotypically severe enough to necessitate appropriate therapy and counseling. Co-inheritance of this nucleotide substitution with other β-thalassemia mutations may account for a considerable portion of the incidence of undiagnosed patients with TI and TM in Guangxi. The IVS-II-5 G>C mutation can pose serious difficulties in screening and counseling. Keywords: β-thalassemia; IVS-II-5 G>C; genotype; phenotype

Date Presented 04/22/2023 Therapeutic service utilization decreased by age and measurement year for the Florida autistic population. Provider referrals and policy changes may sustain access beyond childhood for autistic adults. Primary Author and Speaker: Amber M. Angell Contributing Authors: Susmita Datta, Guangjin Luo, Camille Parchment, Erica Shoemaker, Timothy Reistetter