A disputable presumption of paternity is created if one or more blood tests result in a cumulative paternity index of 99 or greater. If the court or administrator finds that the conclusions of all the experts, as disclosed by the evidence based upon the tests, are that the alleged father is not the father of the child, the question of paternity shall be resolved accordingly. If the experts disagree in their findings or conclusions, the question shall be submitted upon all the evidence. [1953 c.628 § 4; 1985 c.671 § 44b; 1999 c.80 § 27]