Rye has one of the most efficient groups of genes for aluminum tolerance (Alt) among cultivated species of Triticeae. This tolerance is controlled by, at least, three independent and dominant loci (Alt1, Alt2, and Alt3) located on chromosome arms 6RS, 3RS, and 4RL, respectively. The segregation of Alt genes and several random amplified polymorphic DNA (RAPD), Secale cereale inter-microsatellite (SCIM), and Secale cereale microsatellite (SCM) markers in three F(2) between a tolerant cultivar (Ailés) and a non-tolerant inbred line (Riodeva) were studied. The segregation ratio obtained for aluminum tolerance in the three F(2) populations analyzed was 3:1 (tolerant:non-tolerant), indicating that tolerance is controlled by one dominant locus. SCIM811(1376) was linked to an Alt gene in the three F(2) populations studied, and three different SCIMs and one RAPD (SCIM811(1376), SCIM812(626), SCIM812(1138), and OPQ4(725)) were linked to the Alt gene in two F(2) populations. This result indicated that the same Alt gene was segregating in the three crosses. SCIM819(1434) and OPQ4(578) linked to the tolerance gene in one F(2) population were located using wheat-rye ditelosomic addition lines on the 7RS chromosome arm. The Alt locus is mapped between SCIM819(1434) and the OPQ4(578) markers. Two microsatellite loci (SCM-40 and SCM-86), previously located on chromosome 7R, were also linked to the Alt gene. Therefore, the Alt gene segregating in these F(2) populations is new and probably could be orthologous to the Alt genes located on wheat chromosome arm 4DL, on barley chromosome arm 4HL, on rye chromosome arm 4RL, and rice chromosome 3. This new Alt gene located on rye chromosome arm 7RS was named Alt4. A map of rye chromosome 7R with the Alt4 gene, 16 SCIM and RAPD, markers and two SCM markers was obtained.

The biological role in vivo of the homologous CD3γ and δ invariant chains within the human TCR/CD3 complex is a matter of debate, as murine models do not recapitulate human immunodeficiencies. We have characterized, in a Turkish family, two new patients with complete CD3γ deficiency and SCID symptoms and compared them with three CD3γ-deficient individuals belonging to two families from Turkey and Spain. All tested patients shared similar immunological features such as a partial TCR/CD3 expression defect, mild αβ and γδ T lymphocytopenia, poor in vitro proliferative responses to Ags and mitogens at diagnosis, and very low TCR rearrangement excision circles and CD45RA+ αβ T cells. However, intrafamilial and interfamilial clinical variability was observed in patients carrying the same CD3G mutations. Two reached the second or third decade in healthy conditions, whereas the other three showed lethal SCID features with enteropathy early in life. In contrast, all reported human complete CD3δ (or CD3ε) deficiencies are in infants with life-threatening SCID and very severe αβ and γδ T lymphocytopenia. Thus, the peripheral T lymphocyte pool was comparatively well preserved in human CD3γ deficiencies despite poor thymus output or clinical outcome. We propose a CD3δ ≫ CD3γ hierarchy for the relative impact of their absence on the signaling for T cell production in humans.

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The polymerase chain reaction (PCR) was used to locate Sectale cereale (inter-simple sequence repeat ISSR) or Secale cereale inter-microsatellite (SCIM) markers using wheat-rye addition lines in order to develop a set of molecular markers distributed on the seven rye chromosomes. The number of SCIM markers located on 1R, 2R, 3R, 4R, 5R, 6R and 7R chromosomes were 4, 3, 12, 3, 2, 9 and 8, respectively. Therefore, a total of 41 new SCIMs were located on the seven rye chromosomes. The segregation of the 63 different SCIM markers in three different F2 was studied. The observed ISSR segregations were the 3:1 (50.7%), the 15:1 (12.7%) and the 1:1 (14.2%). The linkage analysis carried out indicated that seven of the segregating SCIMs were linked to chromosome 7R and two were linked to chromosome 4R. The use of the SCIM markers as a source of molecular markers that could be linked to interesting genes or other important agronomic traits is discussed.

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