2023 ACMG Annual Clinical Genetics Meeting Digital Edition: Poster Gallery-Detection of non-deletional variants in HBA1 and HBA2 genes through reproductive carrier screening and breakdown by gene, variant, and ethnicity.

Detection of non-deletional variants in HBA1 and HBA2 genes through reproductive carrier screening and breakdown by gene, variant, and ethnicity.

Back to course

Pdf Summary

This study aimed to analyze the reportable variants located on HBA1 versus HBA2 in carrier screening for alpha-thalassemia. The study reviewed carrier screening results of HBA1/2 for over 871,000 cases and performed a retrospective analysis of 1,889 cases positive for non-deletional variants in the HBA1/2 genes. <br /><br />The results showed that 0.22% of cases had a reportable variant, with 30.4% in HBA1 and 69.6% in HBA2. A total of 98 unique variants were identified on HBA1 only, HBA2 only, or both. Among the variants observed at least 20 times, 7 were exclusively detected on HBA1, 11 on HBA2, and 4 on either HBA1 or HBA2 in different individuals. The most common variant in HBA1 was c.358C>T, while the most common variant in HBA2 was c.95+2_95+6delTGAGG.<br /><br />These four variants accounted for 46.7% of all variants in HBA1 and HBA2. The study found that approximately 1 in 455 people had a non-deletional alpha-thal variant, with 2/3 of variants detected in HBA2 and 1/3 in HBA1. The study emphasizes the importance of including the specific gene on carrier screening reports. <br /><br />The authors disclose that they are employees of Natera, Inc. and have stock or options in the company. The study references previous research on alpha-thalassemia.

Asset Subtitle

Co-Author - Emily Becraft, MS, CGC; Co-Author - Elizabeth Repass, ScM, CGC; Co-Author - Chris Villalta, PhD; Co-Author - Amitha S. Sandur, MS; Co-Author - Thu-Ha Nguyen, MB (ASCP), CGMBS; Co-Author - Emily Onyema, MLS (ASCP); Co-Author - Yang Wang, PhD, FACMGG; Co-Author - Xingwu Lu, PhD; Co-Author - Priyanka Arya, PhD, FACMG; Co-Author - Matthew Prego, MS; Co-Author - Wenbo Xu, MD, PhD, FACMG; Presenting Author - Youbao Sha, PhD, FACMG; Submitter Only - J. Bryce Ortiz, PhD;

Meta Tag

Cell free DNA/cfDNA

Genetic Testing

NextGen Sequencing

Sequencing

Variant Detection

Co-Author Emily Becraft, MS, CGC

Co-Author Elizabeth Repass, ScM, CGC

Co-Author Chris Villalta, PhD

Co-Author Amitha S. Sandur, MS

Co-Author Thu-Ha Nguyen, MB (ASCP), CGMBS

Co-Author Emily Onyema, MLS (ASCP)

Co-Author Yang Wang, PhD, FACMGG

Co-Author Xingwu Lu, PhD

Co-Author Priyanka Arya, PhD, FACMG

Co-Author Matthew Prego, MS

Co-Author Wenbo Xu, MD, PhD, FACMG

Presenting Author Youbao Sha, PhD, FACMG

Submitter Only J. Bryce Ortiz, PhD

Keywords

HBA1

HBA2

carrier screening

alpha-thalassemia

reportable variants

non-deletional variants

retrospective analysis

unique variants

c.358C>T

c.95+2_95+6delTGAGG