TABLE 1.
Reported DLGAP5-associated female infertility cases and comparison with the present study.
| Study | Family/patient | Age (years) | Consanguinity | DLGAP5 variant(s) | Zygosity | ART cycles/method | Oocytes retrieved | MII/PB1 oocytes | Fertilization | Key embryological outcome |
|---|---|---|---|---|---|---|---|---|---|---|
| Qu et al., 2025 | Family 1, patient II-1 | 28 | Yes | c.431delA (p.Lys144Argfs*55) | Homozygous | IVF; IVF + ICSI; ICSI ×2 | 39 total | 10/39 (25.6%) | 8 fertilized overall | Predominantly OMA phenotype; only Grade III Day-3 embryos; no pregnancy after transfer |
| Family 1, patient II-2 | 32 | Yes | c.431delA (p.Lys144Argfs*55) | Homozygous | IVF ×2 | 6 | 3/6 (50.0%) | 3 fertilized, with abnormal 3 PN fertilization reported | No usable embryos available | |
| Family 2, patient II-1 | 38 | No | c.847C>G (p.Pro283Ala) + c.1202C>G (p.Thr401Ser) | Compound heterozygous | IVF ×2 | 9 | 9/9 (100%) | 6/9 (66.7%) | Six usable Day-3 embryos; one good-quality blastocyst formed on day 5 but no pregnancy | |
| Wang et al., 2025 | Family 1, patient 1 | NR | Yes | c.1101C>G (p.Tyr367*) | Homozygous | Multiple IVF and/or ICSI cycles | NR | Majority immature | NR | Slow cleavage with developmental arrest around day 3 |
| Family 1, patient 2 (sister) | NR | Yes | c.1101C>G (p.Tyr367*) | Homozygous | Multiple IVF and/or ICSI cycles | NR | Majority immature | NR | Recurrent ART failure with abnormal oocyte maturation | |
| Family 2, patient 1 | NR | No | c.1101C>G (p.Tyr367*) | Homozygous | Three fresh IVF cycles | NR | Majority immature | No embryos available | Cycles terminated because of predominant oocyte immaturity | |
| Hu et al., 2025 | Family 1, patient 1 | 31 | No | c.1101C>T (p.Tyr367Ter) and c.2469_2496del (p.Glu824Valfs*3) | Compound heterozygous | ICSI | 24 across three attempts‡ | 11/16 evaluable (68.8%); first cycle MII NR | 9/11 (81.8%) in evaluable cycles | Cleavage to day 3 occurred, but only two aneuploid blastocysts formed on day 5 |
| Family 2, patient 2 | 30 | No | c.1101C>T (p.Tyr367Ter) and c.517C>T (p.Arg173Ter) | Compound heterozygous | IVF ×2 | 28 | 11/28 (39.3%) | 7/11 (63.6%) | All embryos arrested at the 2–8-cell stage; no blastocysts | |
| Family 3, patient 3 | 31 | Yes | c.1001A>G (p.Asn334Ser) | Homozygous | IVF + ICSI | 13 | 7/13 (53.8%) | 5/7 (71.4%) | One blastocyst formed on day 7; no pregnancy after transfer | |
| Present study | Proband (II.2) | 27 | Yes | NM_014750.5:c.2064-1G>A | Homozygous | ICSI, two stimulated cycles | 11 total | 6/11 (54.5%) | 5/6 (83.3%) | Abnormal oocyte morphology, poor cleavage, and complete failure of blastocyst formation |