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interaction, inheritance, evolution, and health and disease. Given this, sperm DNA methylome
may prove valuable in understanding genotype-phenotype correlations, identifying adaptive and
disease genes, and explaining missing heritability. The analysis overall supports integration of
epigenetic inheritance in modern evolutionary synthesis.

PREVALENCE AND PREDICTORS OF VITAMIN B12 DEFICIENCY: A MULTI-CENTER
A PAN INDIA STUDY ON GENETIC ASSOCIATIONS FOR LOW VITAMIN B12 LEVELS

Vitamin B12, chemically known as cobalamin, is one of the water-soluble vitamins that human
cells cannot produce. Our body acquires vitamin B12 from our diet, usually from animal sources.
Since this vitamin is required for a variety of normal functions including formation of new blood
cells, vitamin B12 deficiency can have systemic effects and is manifested through a wide variety
of symptoms. Inadequate consumption of vitamin B12, especially in vegetarian diet, can lead to
rampant vitamin B12 deficiency which in turn leads to anemia, gastrointestinal and neurological
defects. In some individuals, absorption of vitamin B12 can be defective due to genetic reasons.
Fortification of grains with vitamin B12 is one of the strategies adopted to overcome vitamin B12
deficiency in the population. Shantanu Sengupta’s lab at IGIB is part of a pan-India network to
estimate the extent of vitamin B12 deficiency across the country in different age groups, gender
& evaluate the contribution of vitamin B12 deficiency to the burden of anemia. Some of the
innovative approaches to identify vitamin B12 status, includes the use of a stable isotope labeled
cyanocobalamin to measure B12 absorption and a breath test to be used for functionally
measuring vitamin B12 status. IGIB is also involved in identifying the genetic factors associated
with vitamin B12 levels in the Indian population.

Samples from seven states- Telangana (291), Orissa (278), Madhya Pradesh (291) Gujarat (300),
Meghalaya (273), Tamil Nadu (292) and Assam (296) were received from National Institute of
Nutrition (NIN) for estimation of relevant biochemical parameters. As Vitamin B12 plays an
important role in the 1C metabolism, affecting levels of homocysteine, the relationship between
these two were crucial to understanding whether low vitamin B12 affects homocysteine levels
in these populations. In Telangana, M.P and Orissa, vitamin B12 levels were higher in females
than in males. In the same samples, homocysteine was lower in females than in males. The levels
of vitamin B12 were found to be higher while homocysteine levels were lower in adults. This is
contrary to the current knowledge that vitamin B12 decreases and homocysteine increases with
age. The counterintuitive results obtained are probably due to intake of vitamin B12 pills by
individuals in the adult group. Almost 20 individuals in adult group (>55 years) had vitamin B12
levels more than 1000 pg/ml, while there were none in the younger group. Vitamin B12 levels
were found to be low in Gujarat with a median value of 174.9 pg/ml and a high percentage of
individuals had higher homocysteine levels (90.54%). In Meghalaya, Vitamin B12 (median value
of 349.4) and holoTC (median 60.93) levels were relatively higher and less than 20% of individuals
had low vitamin B12. However, Gujarat’s percentage of individuals with low holoTC was
relatively higher (40%). In Tamil Nadu, vitamin B12 levels were found to be higher with a median
of 394.1 and a lower percentage of individuals had low vitamin B12 (12.45%) that was correlated
with the homocysteine levels, which were found to be low in approximately 58% of the
individuals. Median value for homocysteine is 13.8uM. HDL levels in Meghalaya (median of
33.78) were found to be relatively lower than in Gujarat, with approximately 74% of individuals
having low HDL levels. The levels of holoTC and folate have to be estimated for Tamil Nadu

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