Fann C S, Ott J
Research Foundation for Mental Hygiene, New York State Psychiatric Institute, New York, USA.
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.
在人类遗传图谱中，雌性（xf）和雄性（xm）图谱距离之间的差异可以用比率R = xf/xm或相对差异Q = (xf - xm)/(xf + xm) = (R - 1)/(R + 1)来表征。对于沿染色体分布的遗传标记图谱，Q(d)可被视为Q相对于图谱区间中点d的曲线图。为了估计每个区间的雄性和雌性图谱距离，提出了一种新方法来评估Q(d)沿染色体的最简约趋势，其中Q(d)表示为d的多项式。描述了Q的逐步最大似然多项式回归。该程序已在FORTRAN程序包TREND中实现，并应用于18号染色体的数据。
