A research team at Seoul St. Mary’s Hospital, the Catholic University of Korea has discovered a patient with Hemoglobin Kansas, a type of hemoglobin mutation, for the first time in Korea, the hospital said Wednesday.
The team reported its finding to an international academic journal, the fourth such case following Japan, Brazil, and Turkey, it said.
Hemoglobin is a pigment protein in red blood cells that play a role in transporting oxygen and is determined by the HBA and HBB genes. Hemoglobin mutations can occur due to mutations in these genes and vary from asymptomatic to disease states depending on the variation.
It is known that the oxygen saturation of hemoglobin decreases by inducing the fall in oxygen affinity of the hemoglobin, but in most cases, the person with the mutation does not show any specific symptoms or signs.
The patient in question first came to know her oxygen saturation was lower than average when she gave birth to her first baby (at the age of 34). Oxygen saturation refers to the ratio of the amount of hemoglobin combined with oxygen in the blood against the total amount of hemoglobin as a percentage. When oxygen saturation falls, it is highly likely to cause hypoxia.
The hospital performed arterial blood gas test and cardiovascular- respiratory tests but could not find the cause, as no signs were accompanying to low oxygen saturation.
Eight years later, the patient was pregnant with her third baby and received antenatal examination at the Yeouido St. Mary's Hospital. She was born without any abnormal findings on other tests except for low oxygen saturation. However, the oxygen saturation of the patient's baby also dropped to 92 percent after birth. The average range was from 95 to 100 percent, and when it’s less than 90 percent, a dangerous situation can occur leading to hypoxia.
When the baby was supplied with oxygen, the oxygen saturation rose, but the oxygen saturation fell again when the oxygen supply stopped, and the process repeated. The medical staff suspected that there was hemoglobin problem in the patient's family and requested the patient to the genetic diagnosis center of Seoul St. Mary's Hospital.
The center confirmed the patient’s grandmother and father also had low oxygen saturation, and their DNA was isolated by hemoglobin electrophoresis, differential diagnosis of Mediterranean anemia and hemochromatosis, and HBB gene test.
The team confirmed the substitution of the 103rd amino acid of the HBB gene through direct sequencing analysis of individual genes and confirmed that this point mutation causes hemoglobin Kansas, a type of the hemoglobin mutation.
|Professor Kim Myung-shin of the Seoul St. Mary’s Hospital, The Catholic University of Korea played a key role in discovering Korea’s first patient with Hemoglobin Kansas.|
"Some of the various mutations of hemoglobin can be detected through hemoglobin electrophoresis, but there are many cases where this is not the case, so genetic analysis using direct sequencing will be of great help in identifying new variants and variations as in this patient,” Professor Kim Myung-shin said. “This study is meaningful in that it has diagnosed a rare mutation rare disease globally.”
Professor Kim went to say, “And if we find as many treatable genetic mutations as possible, it will help to improve the quality of life of patients by providing the optimal treatment plan for the individual and avoiding incorrect treatment.”
The study was published in the March issue of the Annals of Laboratory Medicine, a Science Citation Index (SCI) academic journal of the Korean Society for Laboratory Medicine.
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