Genomic imprinting occurs in both male and female gametes during gametogenesis, but the
exact time when imprinting begins and ends is unknown. In the present study we injected …

Normally, round spermatids, the youngest male germ cells with a set of haploid
chromosomes, cannot fertilize mature oocytes. However, when mouse spermatids were …

This study shows that the nucleus of the secondary spermatocyte can participate in syngamy
and normal embryonic development. Spermatogenic cells were released from the …

The advent of human round spermatid microinjection (ROSI) into oocytes as a treatment for
severe male infertility raises the question of whether spermatids have undergone all of the …

Primary spermatocytes are the male germ cells before meiosis I. To examine whether these
4n diploid cells are genetically competent to fertilize oocytes and support full embryo …

A mature motile mouse spermatozoon was microinjected under the zona pellucida of mouse
eggs. Twenty-five percent of eggs were fertilized, and 54% of these developed to normal …

Although great progress has been made in both the investigation and treatment of infertility,
a considerable number of patients still fail to conceive. Spermatogenic failure and/or oocyte …

There are distinctive and characteristic genomic modifications in primordial germ cells that
distinguish the germ cell lineage from somatic cells. These modifications include, genome …

We wish to report the successful fertilization of a human oocyte by a late-stage spermatid by
the use of intracytoplasmic sperm injection (ICSI). Our previous work has shown that …

Due to the existence of ample background information on its reproduction, embryology and
genetics, the mouse is potentially an excellent animal model for intracytoplasmic sperm …