Parsimonious estimation of sex-specific map distances by stepwise maximum likelihood regression

Genomics. 1995 Oct 10;29(3):571-5. doi: 10.1006/geno.1995.9964.


In human genetic maps, differences between female (xf) and male (xm) map distances may be characterized by the ratio, R = xf/xm, or the relative difference, Q = (xf - xm)/(xf + xm) = (R - 1)/(R + 1). For a map of genetic markers spread along a chromosome, Q(d) may be viewed as a graph of Q versus the midpoints, d, of the map intervals. To estimate male and female map distances for each interval, a novel method is proposed to evaluate the most parsimonious trend of Q(d) along the chromosome, where Q(d) is expressed as a polynomial in d. Stepwise maximum likelihood polynomial regression of Q is described. The procedure has been implemented in a FORTRAN program package, TREND, and is applied to data on chromosome 18.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Chromosomes, Human*
  • Chromosomes, Human, Pair 18
  • Female
  • Genetic Markers
  • Genetics, Medical*
  • Humans
  • Male
  • Models, Genetic*
  • Models, Theoretical
  • Probability
  • Regression Analysis
  • Sex Characteristics*


  • Genetic Markers