Recent studies have suggested that sex-specific genetic architecture could be because of the effects of autosomal genes that are differentially expressed in males and females. Yet, few studies have explored the effects of X-linked genes on sex-specific genetic architecture. In this study, we extended the variance component, maximum likelihood method to evaluate the relative contributions of sex...

OBJECTIVE To compare the karyotype of babies conceived through ICSI with that of naturally conceived babies. DESIGN Prospective controlled study. SETTING The Egyptian IVF-ET Center, Cairo, Egypt. PATIENT(S) Four hundred and thirty babies conceived through ICSI and 430 babies conceived naturally. INTERVENTION(S) ICSI and karyotyping. MAIN OUTCOME MEASURE(S) Abnormal karyotype. RESULT...

X-linked genes can evolve slower or faster depending on whether most recessive, or at least partially recessive alleles are deleterious or beneficial due to their hemizygous expression in males. Molecular studies of X chromosome divergence have provided conflicting evidence for both a higher and lower rate of nucleotide substitution at both synonymous and nonsynonymous sites, depending on the n...

EARLIER papers (MERRELL 1953a, b; MERRELL and UNDERHILL 1956) explored the effects of competition between sex-linked and autosomal recessives and their wild-type alleles in experimental populations of Drosophila melanogaster. FALCONER (1960) has used data from one of these papers (1953b) to show the change in gene frequency under selection of a sex-linked gene, commenting that “there is no well...

The sex-ratio trait that exists in a dozen Drosophila species is a case of naturally occurring X chromosome drive that causes males to produce female-biased progeny. Autosomal and Y polymorphism for suppressors are known to cause variation in drive expression, but the X chromosome polymorphism has never been thoroughly investigated. We characterized 41 X chromosomes from a natural population of...

We report two opposite-sex siblings with the severe infantile form of nemaline myopathy; diagnoses were made on muscle biopsy. Neither parent showed clinical or electromyographic evidence of myopathy, and both had negative muscle biopsies. Autosomal recessive inheritance seems likely.