Albinism is a group of inherited situations that results in little or no pigment (hypopigmentation) in the eyes alone or the eyes, skin, and hair. Inheriting a changed copy of a gene that does not work agreeably is the cause of most types of albinism. Mutations in many genes were described in different types of albinism in humans. Albinism is known to impress mammals, birds, fish, reptiles, and amphibians (Fertl & Rosel, 2009). Is this genetic condition seen only limited to the animal kingdom?
Chloroplasts, a type of plastid, are very important to plants. Chloroplasts enable the plant to produce its required energy through photosynthesis but also play a role in creating many plant hormones and pigments (Pogson et al., 2015). One of these pigments is chlorophyll, which gives the plant its green color and takes a role in the photosynthesis mechanism (Prashanti et al., 2022).

Mutation of leaf color was detected in many plants. As a result of these mutations, the plant either remains chlorophyll-free or suffers from chlorophyll deficiency. An increase in reactive oxygen species (ROS) was observed when these mutants were exposed to light (Sakowska et al., 2018). These oxygen species, caused by excessive light, can create an oxidative effect and cause the plant to turn white or die. Some of the albino mutants were affected by environmental conditions. The defect in the functioning of the OsABCI8 protein caused albino leaves to occur in rice during periods of heavy rain and to turn green again during periods of reduced rain (Zeng et al., 2017).
Another example is the D-WB((Dwarfing, White leaves and Blue grains) hybrid, which is the result of crossing two different wheat (Triticum aestivum L.) species Lango and Indian Blue Grain. The leaves of DW-B show albinism after flowering at low temperatures and then turning green with increasing temperature. Studies have been done between these three wheat species when D-WB is green, albino, and turning green. In these three stages, the lowest photosynthesis rate was recorded when all leaves were albino. Therefore, the decrease in the level of photosynthetic gene expression inhibited the photosynthetic efficiency and capacity of DW-B plants. It provided evidence that the reduction in photosynthetic rate may be one of the causes of DW-B’s albinism. These results suggested that low chlorophyll levels may be the primary cause of the low photosynthetic efficiency of DW-B and the abnormal leaf color phenotype (Sun et al., 2023).
Another study on albino plants was performed on a cucumber albino alc mutant that presented white cotyledons under normal light conditions and failed to produce the first actual leaf. The alc mutant developed creamy green cotyledons under dim light but died after exposure to normal light. These mutant denatured chloroplast structures were observed by electron microscopy. Comparative transcriptomic analysis between the alc mutant and wild type revealed that the genes involved in chloroplast development of the FtsH gene and the PPR gene had negligible expression in the mutant (Yan et al., 2022).

It seems that albinism can occur for many different species and for many different reasons. These reasons may be caused by many genetic or environmental factors, but the main problem is the defect in the chloroplast, which meets the energy needs of plants, or in the chlorophyll, which is a color pigment.
References:
- Fertl, D., & Rosel, P. E. (2009). Albinism. Encyclopedia of Marine Mammals, 24–26. https://doi.org/10.1016/B978-0-12-373553-9.00006-7
- Pogson, B. J., Ganguly, D., & Albrecht-Borth, V. (2015). Insights into chloroplast biogenesis and development. Biochimica et Biophysica Acta (BBA) – Bioenergetics, 1847(9), 1017–1024. https://doi.org/10.1016/J.BBABIO.2015.02.003
- Prashanti, B., Sreevani, I., & Venkateswarlu, G. (2022). Estimation of chlorophyll pigment in cyamopsis tetragonoloba Estimation of Chlorophyll Pigment in Cyamopsis tetragonoloba (Cluster bean) in Different Soil Samples. https://doi.org/10.9734/bpi/rabs/v9cle/view/8348
- Sakowska, K., Alberti, G., Genesio, L., Peressotti, A., Delle Vedove, G., Gianelle, D., Colombo, R., Rodeghiero, M., Panigada, C., Juszczak, R., Celesti, M., Rossini, M., Haworth, M., Campbell, B. W., Mevy, J. P., Vescovo, L., Cendrero-Mateo, M. P., Rascher, U., & Miglietta, F. (2018). Leaf and canopy photosynthesis of a chlorophyll deficient soybean mutant. Plant Cell and Environment, 41(6), 1427–1437. https://doi.org/10.1111/pce.13180
- Zeng, X., Tang, R., Guo, H., Ke, S., Teng, B., Hung, Y. H., Xu, Z., Xie, X. M., Hsieh, T. F., & Zhang, X. Q. (2017). A naturally occurring conditional albino mutant in rice caused by defects in the plastid-localized OsABCI8 transporter. Plant Molecular Biology, 94(1–2), 137–148. https://doi.org/10.1007/s11103-017-0598-4
- Sun, F., Ye, W., Li, S., Wang, Z., Xie, K., Wang, W., Zhang, C., & Xi, Y. (2023). Analysis of agronomic traits and regulatory mechanism of a semi-dwarf, albino and blue grain wheat line. https://doi.org/10.21203/rs.3.rs-2477850/v1
- Yan, J., Liu, B., Cao, Z., Chen, L., Liang, Z., Wang, M., Liu, W., Lin, Y., & Jiang, B. (2022). Cytological, genetic and transcriptomic characterization of a cucumber albino mutant. Frontiers in Plant Science, 13. https://doi.org/10.3389/fpls.2022.1047090
Figure References:
- Mutant Orchids Have a lot to Teach Us About Parasitic Plants. Available from: https://www.indefenseofplants.com/blog/tag/albino+plants [accessed Feb 20 2023].
- Cytological, genetic and transcriptomic characterization of a cucumber albino mutant. Available from: https://www.researchgate.net/publication/364595288_Cytological_genetic_and_transcriptomic_characterization_of_a_cucumber_albino_mutant [accessed Feb 20 2023].
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