97. A rare case of low-hypodiploid acute lymphoblastic leukemia

Aly Abdelkareem

Morteza Seifi

Dr. Morteza Seifi is a Laboratory Genetics and Genomics (LGG) fellow at the University of Wisconsin-Madison (UW-Madison). With a Ph.D. in Medical Genetics from the esteemed University of Alberta, AB, Canada, Dr. Seifi has gained invaluable experience in the field of genetics and genomics. Prior to joining UW-Madison, he held the position of post-doctoral fellow at the renowned Alberta Children’s Hospital at the University of Calgary, AB, Canada.

During his time at the Alberta Children’s Hospital, Dr. Seifi was instrumental in supporting activity 2 of the Care for Rare Solve program (CARE4RARE.CA). The program aimed to identify the genetic and genomic basis for rare unsolved diseases using a combination of novel next-generation sequencing (NGS)-based technologies and wet-lab techniques. Dr. Seifi’s focus on this area has equipped him with the skills and knowledge required to identify rare genetic disorders and provide personalized healthcare to patients.

Dr. Seifi is particularly interested in integrating novel molecular and cytogenetic diagnostic approaches into the clinical care of patients with genetic disorders. He firmly believes that by doing so, he can help find clinical genomic answers in these patients and advance their personalized healthcare. Dr. Seifi’s expertise and contributions have been recognized through the publication of several peer-reviewed journal articles and his presentations at various national and international conferences.


Morteza Seifia, Randee Blumera, Amber Waltersa, Erin Baldwina, Eric Johnsona, Xiangqiang Shaob, Vanessa Hornerc

aWisconsin State Laboratory of Hygiene, UW Madison, Madison, WI, United States; bUW Madison, Madison, WI, United States; cUW Madison, Madison, WI, United States

Low hypodiploid (31-39 chromosomes) is a rare subtype of childhood and adult B-cell precursor acute lymphocytic leukemia (ALL) associated with very poor diagnosis. It is characterized by a non-random pattern of chromosome losses and a distinct mutational profile with frequent loss-of-function mutations of TP53 (approximately half of which are germline in childhood low-hypodiploid ALL), as well as aberrations of IKZF2, RB1, and CDKN2A/B.

We report a 21-year-old male with B-cell ALL. Conventional cytogenetic and fluorescence in situ hybridization (FISH) analyses showed four related abnormal clones. The first clone showed an abnormal low-hypodiploid clone with loss of one copy of all chromosomes (except chromosomes X, 5, 8, 9, 14, 18, 19, 21, and 22), deletion of most of the long arm of one of the chromosomes 14 homologs from 14q22 to 14qter, and an unbalanced translocation between chromosomes 11 and 22. The subclones (three clones with increasing modal chromosome numbers) showed an approximate doubling of the chromosomal content of the first clone with relative gain or loss of several chromosomes. Microarray analysis was consistent with chromosome and FISH findings, and it also showed an RB1 gene deletion in this patient, which is consistent with the gene mutation signatures of low hypodiploid  ALL. Therefore, the patient is low-hypodiploid and shows the hyperdiploid subclone due to endoreduplication (replication of genome without cytokinesis) of the primary low-hypodiploid clone. Our study highlights the integration of microarray, karyotyping, and FISH as powerful techniques to provide a practical, sensitive and specifiLow