Journal of Human Genetics (2009) 54, 56–61; doi:10.1038/jhg.2008.3; published online 9 January 2009

The Author name Hiroko Taniai was published incorrectly in the above referenced paper. The correct author list is shown above.

The sentence mentioned below including the equation was also published incorrectly in the above referenced paper.

where x1 and x2 are variables for integration over the normal distribution of CARS score for a proband and his co-twin, y1 and y2 are variables of IQ score for a proband and his co-twin, ϕ is the four-variate normal probability density function, R is the correlation matrix (transformed from the covariance matrix), and t is the threshold used for ascertainment.

The correct sentence is shown below.

where x1 and x2 are variables for integration over the normal distribution of CARS score for individuals 1 and 2, y1 and y2 are variables of IQ score for individuals 1 and 2, ϕ is the four-variate normal probability density function, R is the correlation matrix (transformed from the covariance matrix), and t is the threshold used for ascertainment.

The corresponding author would like to apologize for these errors.