Inheritance of brachydactyly type D.

Inheritance of brachydactyly type D (BD-D) was studied in two unreported Caucasian family pedigrees and in 36 previously reported family pedigrees. The inheritance pattern was characteristic of a single autosomal dominant gene with incomplete penetrance. Using the proportion of individuals exhibiting the trait as the index, penetrance was sex influenced, being complete in females and approximately 62 percent in males. Expression of BD-D in both females and males was bilateral (both thumbs) for approximately three-fourths and unilateral (either right or left thumb) for approximately one-fourth of the individuals.

Desired family size and sex of children in Nigeria.

During 1981, sex ratio data and preferences for family size and for combinations and permutations of children were provided by 333 Nigerian students at the University of Ilorin, Ilorin, Nigeria. For the present and parental generations combined, the secondary sex ratio was estimated to be 95.8 males:100 females. In the projected families, preferences for family sizes resulted in an average of 4.88 children per family. The most preferred family consisted of four children--a 2m2f combination in a mfmf order, whereas the second most preferred family consisted of five children--3m2f combination in a mfmfm order. Also expressed was a strong preference for permutations of sexes, resulting in a male child as first-born followed by an alternation of sexes. A greater preference for male children was indicated by the combined sex ratio of 167 males:100 females for the preferred families.

Distribution of sexes in cattle.

Data were obtained from records of 1,046 Holstein dams included in the dairy herd at Cornell University during the years 1940 through 1977. Sex by order of parity was determined for the offspring of each dam. The overall sex ratio for 4,245 single parities was 52.74 percent males. Sex ratios for different parities were relatively consistent. Within progenies of the dams, there was no consistent evidence of association between the sexes of successive and various nonsuccessive calves. Frequencies of combinations of sexes in the different sizes of offspring occurred as expected.

Desired family size and sex of children in Botucatu, Brazil.

During 1977--78, 715 unmarried college students at the Universidade Estadual Paulista, Botucatu, Brazil, were surveyed for their preferences for family sizes and combinations and permutations of sexes of children. The most preferred family size by both male and female respondents was two children. A slightly lower proportion of respondents preferred a family size of three children. Average size of the desired families was approximately 2.76 children. The most preferred combinations of sexes were one male, one female; one female, two males; and two females, two males, respectively, in families of two, three, and four children. Preferred permutations of sexes were those in which the first child was male and subsequent children resulted in an alternation of sexes.