CHICAGO - A GENES marker which makes some people more likely to be hooked on cigarettes could also allow them to drink their friends under the table by dampening their body's response to alcohol, according to a study published on Monday.

Several previous studies have found that this particular group of chromosomes also makes people more likely to develop lung cancer or become alcoholics.

Earlier studies have also found that people with a low response to alcohol are at an increased risk of becoming alcoholics and that both traits are inheritable.

So researchers tested 367 siblings to see if this group of chromosomes also impacted the body's level of response to alcohol.

While they were unable to isolate it to a single gene, they found a strong association between genetic mutations in this chromosome group and how many drinks it took for the subjects to begin to sway from the affects of alcohol.

'These findings confirm that alcohol level of response, an intermediate phenotype associated with alcohol dependence and abuse, is influenced by a genetic component,' wrote lead author Geoff Joslyn of the Ernest Gallo Clinic and Research Center.

The findings also give 'strong support' to the potential use of alcohol response levels to determine whether someone has a genetic susceptibility to alcoholism and 'will prove valuable in the identification of other genetic loci conferring susceptibility to alcohol use disorders', he wrote.

The study was published in the Proceedings of the National Academy of Sciences. -- AFP