Sdad assay and uses thereof

Abstract

Methods for screening human sperm using a sperm DNA accelerated decondensation (SDAD) Test, readable at a 5 minute time point, are disclosed. The method is useful in the screening and clinical management for a reproductively challenged human couple. The methods disclosed are highly predictive of ICSI outcome. Methods for screening human sperm using a sperm DNA decondensation (SDD) Test, readable at a 15 minute time point, are disclosed. This test is highly predictive of IUI and IVF outcome. Also dislosed are methods for selecting an appropriate assisted reproductive technique (ART) for a reproductively challenged couple. These methods provide a decision tree that employs a patient's sperm test results in a sperm DNA accelerated decondensation (SDAD) Test, and sperm DNA decondensation (SDD) Test, wherein an appropriate assisted technique may be selected from intrauterine insemination (IUI), IVF or ICSI. Also, methods are described that will identify males who may benefit from anti-oxidant therapy and / or a varicocelectomy before using their sperm in ART. An automated scoring method is also disclosed for assessing sperm activity after a 5-minute incubation in egg extract (SDAD Test), and after a 15-minute incubation in egg extract (SDD Test). Finally, an automated sperm processing protocol is also disclosed for the rapid preparation of sperm for analysis in both the SDD and SDAD Tests.

Description

PRIORITY CLAIM[0001]This application is a non-provisional of, claims priority to and the benefit of U.S. Provisional Patent Application Ser. No. 60 / 957,117, filed on Aug. 21, 2007, the entire contents of which are incorporated herein by reference.BACKGROUND OF INVENTION[0002]The process of fertilization involves a series of events including: a) sperm binding to, and then penetration of the oocyte zona pellucida via the acrosome reaction, b) sperm fusion with the oocyte plasma membrane, c) oocyte activation (release of the cortical granules to prevent multiple sperm from fertilizing the egg), d) sperm activation and pronucleous formation (Abou-Haila A. et al. 2000: Furlong, L. et al. 2005).[0003]Sperm activation initiates post-fertilization upon entry into the ooplasm where the compacted sperm DNA undergoes many alterations as it develops into a male pronucleus. During the first phase of sperm activation or decondensation, the chromatin condensation acquired during spermiogenesis is ...

AI Technical Summary

Benefits of technology

[0007]In some embodiments, a screening method is provided that is useful in identifying male sperm donors who will have a low probability of successful ART attempts at pregnancy (success being defined as live birth), such as when using ICSI. Other sperm screening assays, such as the sperm DNA decondensation (SDD) Test, the sperm penetration assay (SPA), and the sperm chromatin structure assay (SCSA) have all been found to not be predictive of ICSI live birth outcome. Thus, in some aspect, the present disclosure describes a screening method that can predict ICSI outcome. In some embodiments, this screening method comprises obtaining a semen sample from a potential sperm donor that has been determined to provide a normal sperm assay result in a SPA and SDD Test, and assessing the sample for sperm DNA accelerated decondensation (SDAD) in a frog egg extract as described herein. In some embodiments, the sperm DNA accelerated decondensation (SDAD) is a measure of chromatin DNA decondensation evidenced after about a 5 (five) minute incubation interval in a frog egg extract. In other embodiments, a sperm sample with essentially complete sperm chromatin DNA decondesation at the five (5) minute time interval identifies an unsatisfactory sperm donor for an ICSI pregnancy attempt.

Problems solved by technology

The screening method has relatively low predictive capacity for determining a couple's success, success being defined as live birth, when sperm from the male partner is used in an ICSI attempt at pregnancy.

However, because the SDD Test has no predictive capacity for determining if a patient will succeed in an ICSI attempt at pregnancy, such patients can go directly to ICSI attempts at pregnancy.

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