Funding for this research was provided by:
Vietnam Academy of Science and Technology (KHCBSS.02/18-20)
Received: 1 September 2020
Accepted: 19 December 2020
First Online: 18 January 2021
Compliance with ethical standards
: Thu Hien Nguyen, Ngoc-Lan Nguyen, Chi Dung Vu, Can Thi Bich Ngoc, Ngoc Khanh Nguyen, Huy Hoang Nguyen declare that they have no conflict of interest.
: This study was conducted in accordance with the Declaration of Helsinki and the protocol was approved by the Ethics Committee of the Institute of Genome Research (Institute of Genome Research Institutional Review Board, Hanoi, Vietnam, Reference no: 18/QD-NCHG on 22 March 2018).
: Written informed consent were obtained from the parents.
: The parents provided informed consent for publication of the images in Figs. 1 and 2a and b.