Molecular diagnosis of hereditary spherocytosis by multi-gene target sequencing in Korea: matching with osmotic fragility test and presence of spherocyte

Hyoung Soo Choi†,
Qute Choi†,
Jung-Ah Kim,
Kyong Ok Im,
Si Nae Park,
Yoomi Park,
Hee Young Shin,
Hyoung Jin Kang,
Hoon Kook,
Seon Young Kim,
Soo-Jeong Kim,
Inho Kim,
Ji Yoon Kim,
Hawk Kim,
Kyung Duk Park,
Kyung Bae Park,
Meerim Park,
Sang Kyu Park,
Eun Sil Park,
Jeong-A Park,
Jun Eun Park,
Ji Kyoung Park,
Hee Jo Baek,
Jeong Ho Seo,
Ye Jee Shim,
Hyo Seop Ahn,
Keon Hee Yoo,
Hoi Soo Yoon,
Young-Woong Won,
Kun Soo Lee,
Kwang Chul Lee,
Mee Jeong Lee,
Sun Ah. Lee,
Jun Ah Lee,
Jae Min Lee,
Jae Hee Lee,
Ji Won Lee,
Young Tak Lim,
Hyun Joo Jung,
Hee Won Chueh,
Eun Jin Choi,
Hye Lim Jung,
Ju Han Kim†Email author,
Dong Soon Lee†Email author and
The Hereditary Hemolytic Anemia Working Party of the Korean Society of Hematology

†Contributed equally

Orphanet Journal of Rare Diseases201914:114

https://doi.org/10.1186/s13023-019-1070-0

Received: 1 December 2018
Accepted: 17 April 2019
Published: 23 May 2019

Abstract

Background

Current diagnostic tests for hereditary spherocytosis (HS) focus on the detection of hemolysis or indirectly assessing defects of membrane protein, whereas direct methods to detect protein defects are complicated and difficult to implement. In the present study, we investigated the patterns of genetic variation associated with HS among patients clinically diagnosed with HS.

Methods

Multi-gene targeted sequencing of 43 genes (17 RBC membrane protein-encoding genes, 20 RBC enzyme-encoding genes, and six additional genes for the differential diagnosis) was performed using the Illumina HiSeq platform.

Results

Among 59 patients with HS, 50 (84.7%) had one or more significant variants in a RBC membrane protein-encoding genes. A total of 54 significant variants including 46 novel mutations were detected in six RBC membrane protein-encoding genes, with the highest number of variants found in SPTB (n = 28), and followed by ANK1 (n = 19), SLC4A1 (n = 3), SPTA1 (n = 2), EPB41 (n = 1), and EPB42 (n = 1). Concurrent mutations of genes encoding RBC enzymes (ALDOB, GAPDH, and GSR) were detected in three patients. UGT1A1 mutations were present in 24 patients (40.7%). Positive rate of osmotic fragility test was 86.8% among patients harboring HS-related gene mutations.

Conclusions

This constitutes the first large-scaled genetic study of Korean patients with HS. We demonstrated that multi-gene target sequencing is sensitive and feasible that can be used as a powerful tool for diagnosing HS. Considering the discrepancies of clinical and molecular diagnoses of HS, our findings suggest that molecular genetic analysis is required for accurate diagnosis of HS.