ABO Group Types Linked To Overweight And Obesity

There is great genetic diversity within all human populations, and a simple example is the ABO group system. Many studies have supported a number of associations between ABO blood type and certain diseases, including pancreatic cancer, venous thromboembolism, and myocardial infarction in the presence of coronary atherosclerosis, sexual maturity, breast cancer, cancer, infections, diabetes mellitus, cardiovascular diseases, hypertension, peptic ulcers, intelligence, socioeconomic class, personality, suicide, BMI, and obesity.

Meanwhile, new research accepted to be published in the journal Obesity Medicine in March 2019, suggests that “in the ABO blood group system, group AB was more susceptible to develop overweight and obesity in the Kurd race.”

The research team looked at types of ABO blood groups as a cause of overweight and obesity. Overweight and obesity have emerged as one of the most serious public health concerns of the 21st century, which is a predictor of remarkable morbidity and mortality. There are studies claiming relation of ABO blood groups to overweight and obesity, while some others denied any association.

The prevalence of overweight and obesity in 2014 in the Sulaimani province was 20.6% and 11.3%, and it is rising. Now there is more awareness about this subject and its risks. In the ABO system, the most common phenotype in Kurdistan was O (37%), followed by A (32.6%), B (22.8%), and AB(7.6%). This is intermediate between the European and Asian countries, with some specificity to the Kurds’ population, reflecting the distinct geographical area and preserved ethnic background of the Kurds in the region.

To avoid bias, the frequency of ABO group types in an area of the Sulemani Governorate, which is pure Kurds, was evaluated and compared to an assay done in South Kurdistan, (inhabited also by non-Kurds like Arabic, Assyrian Neo-Aramaic, Chaldean Neo-Aramaic, Turkmen, and Armenian). “Ninety-eight percent of the citizens in Sulaimani Governorate are Kurds. They are traditionally regarded as Iranians and of Iranian origin, and therefore as Indo-Europeans, mainly because they speak Iranian.”

“Newest DNA-research of advanced Human Anthropology indicates that the Oldest ancestral forefathers of Kurds were millennia later linguistically Iranianized in several waves by militarily organized elites of (R1a1) immigrants from Central Asia.” Izady argues that the period from the 5th century BC through the 6th century AD “marks the homogenization and consolidation of the modern Kurdish national identity.”

The ethnic designator of Kurds was finally established and applied to all segments of the nation. ABO and rhesus (Rh) genes and phenotypes vary widely between ethnic groups both within and between geographical areas; for this reason, the city was selected to avoid the bias of biological difference and mixed ethnic groups to have the least biological differences. It became clear from the results that all ABO groups (O= 37.80%, A = 31.94%, B = 22.90%, AB= 07.36%) were different significantly from Iranian ABO groups (O= 29.75%, A = 21.50%, B = 34.84%, AB= 13.91%) especially in (8.05%) difference Group O and (6.55%) difference in the Group AB.

The same was right regarding significant differences with Turks (O= 34.83%, A = 42.42%, B = 14.89%, AB= 7.86%) and Iraqi non-Kurds (O= 36.00%, A = 30.00%, B = 28.00%, AB= 08.00%) in all types of the ABO group system.

Different blood types may produce considerable physiological differences and susceptibility to diseases. The ABO blood group system is considered as a genetic marker for diseases and obesity, but there is still a wide controversy regarding the link between ABO group types to weight problems. There are articles support this linkage as well as studies which deny any association.

One may notice that the most common type of ABO groups in the Sulemani governorate is group O (37.80%). 40.80% of the overweight and obese patients were of group O, but with no statistical significance (P= 0.4613). Meanwhile, there was a relatively large number (11.41%) of the overweight and obese patients in the rarest group, AB (07.36%), with statistically highly significant difference. Aboel-Fetoh et al. found this association between ABO blood groups and overweight and obesity to group AB, and Kelso et al. found the relation of group AB to Diabetes Mellitus and obesity. Meanwhile, Nwafor Chuemere et al. found the link between group B and obesity and Diabetes Mellitus. The same link was  found by Qunq and Abdel Hamid. A high incidence of obesity in Malaysia was found in type B by Chandra Kala Rai and Sapkota, with findings indicating maximum obesity in blood group B, but no obesity in blood group AB.

In the ratio of the ABO groups in obese and overweight patients compared to other works, we showed that the AB group in the overweight and obese group in the current study was higher than others. The O:A:B: AB ratio in the work of Chuemere et al. was 15:4:3:1, Jafari et al. was 03:4:3;1, Selçuk Nas and Fiskin was 01:1:1:1, Samuel SmithIsaac Abaidooet al. was 17:6:8:1, AboelFetoh et al. was 07:5:3:1, versus the present work’s O:A:B:AB ratio was 08:6:3:2. This may explain the statistical correlation between AB blood groups and overweight and obesity because the ratio of the AB group in the patients in other studies was (:1) versus (:2) in the present work.

The highest prevalence of overweight and obesity in blood group AB only means that blood group AB may have a link with overweight and obesity in this particular area and this population who are of the same race. This couldn’t be generalized to any other area with a different race or ethnic groups. This may mean every race or ethnic group may need its own special study to evaluate any link between the ABO blood group system and weight gain.

These findings are described in the article entitled Association of ABO group types to overweight and obesity: Based on six years of experience in two centers in Sulaimani governorate, Kurdistan Region/Iraq, recently published in the journal Obesity Medicine. This work was conducted by Hiwa Omer Ahmed, et al., from the University of Sulaimani and Sulaimani Teaching Hospital.