Tomone Yano

Sexing ofin vitro-fertilized preimplantation mouse embryos by the PCR method

SummaryThe applicability of the dual PCR method to embryo sexing was examined with the aim of establishing a noninvasive method of preimplantation diagnosis for human genetic disorders. Mouse pre-embryos obtained by in vitro fertilization were studied. The Sry gene sequence and the myogenin sequence were amplified as the Y-specific and internal control sequences, respectively. Amplification of as little as 10 pg of mouse genomic DNA was possible with the dual PCR method, the sensitivity being 10-fold greater than that of the single PCR method. The sex was identified in 100% (24/24) and 96% (23/24) of the pre-embryos tested at the 16- and 4-cell stages, respectively. In addition, the sex of all four single blastomeres dissociated from 4-cell pre-embryos agreed in 76% (16/21) of the specimens tested and 94% (79/84) of dissociated blastomeres could be sexed. The sex of single blastomeres biopsied from pre-embryos at the 8-cell stage could be identified. After transfer of 13 male and 25 female sexed pre-embryos, six viable fetuses were obtained. Histological examination showed that all these fetuses were of the predicted sex.Sexing of biopsied single blastomeres by the dual PCR method was rapid and reliable, suggesting its feasibility for preimplantation diagnosis of in vitro fertilized human pre-embryos.

Deletion detection for diagnosis of Duchenne muscular dystrophy in the Japanese population—Comparisom between the polymerase chain reaction and the Southern blot analysis

SummaryWe compared the efficacy of the multiplex PCR with that of the cDNA analysis for detection of deletions of the DMD gene in the Japanese patients. Thirty males with DMD from 27 Japanese families were studied by the multiplex PCR, and 24 of them were also investigated by Southern blot analysis. We used five dystrophin cDNA probes for deletion analysis. A total of 19 regions were amplified by the PCR to detect deletions, 9 regions by the method of Chamberlain et al. and another 10 regions by the method of Beggs et al. Deletions were detected in 14 (52%) out of 27 DMD families by the PCR. Southern blot analysis detected deletions in 14 (64%) out of 22 families. Thirteen (93%) of the 14 DMD families with deletions detected by Southern blotting were also confirmed by the multiplex PCR. Provided care is taken in cases where the deletion is limited to a single exon, the multiplex PCR appears to be an efficient and useful alternative to conventional Southern blot analysis for detecting deletions during the prenatal and postnatal diagnosis of DMD.

Spontaneous ectopic pregnancy occurring in the remnant tube after ipsilateral salpingectomy: a report of 2 cases

Ectopic pregnancy occurring in the remnant tube after ipsilateral salpingectomy is assumed to be rare. We report 2 cases of spontaneous ectopic pregnancy occurring in the remnant tube that were treated surgically. Even in spontaneous pregnancy, attention should be paid to the remnant tube so as not to miss an ectopic pregnancy after previous salpingectomy.

Prenatal Diagnosis of Duchenne Muscular Dystrophy by Polymerase Chain Reaction Analysis

The efficacy of the polymerase chain reaction (PCR) in the first-trimester prenatal diagnosis of Duchenne muscular dystrophy (DMD) was examined. Twenty-seven fetuses from 26 Japanese pedigrees at risk for DMD were analyzed. PCR-restriction fragment length polymorphism analysis, multiplex PCR, and dinucleotide repeat polymorphism analysis were used. Of 16 males, 11 were determined to be unaffected, 4 were affected, and the remaining 1 was undetermined. Of the 11 female fetuses, 1 was diagnosed as a noncarrier, 4 were carriers, and the carrier status of the remaining 6 was not determined at the option of the patients, although DNA polymorphisms could be detected in those patients. Prenatal diagnosis by PCR analysis was possible in 96% of the fetuses tested (26 of 27).

Nonpuerperal uterine inversion due to submucous leiomyoma

Uterine inversion is a rare complication of the postpartum period and an even rarer complication of the nonpuerperal period. A 47-year-old woman, gravid 2, para 2, was referred to our hospital with blood-stained leucorrhoea and severe anemia. Magnetic resonance imaging (MRI) scans showed a U-shaped uterine cavity and the pedicles of a tumor attached to the uterine fundi. The patient underwent an abdominal hysterectomy. The diagnosis of uterine inversion was confirmed during the operation. MRI should be performed for the diagnosis of this rare disease.